1 /* 2 BlueZ - Bluetooth protocol stack for Linux 3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License version 2 as 7 published by the Free Software Foundation; 8 9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. 12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY 13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 20 SOFTWARE IS DISCLAIMED. 21 */ 22 23 #include <linux/debugfs.h> 24 #include <linux/scatterlist.h> 25 #include <linux/crypto.h> 26 #include <crypto/aes.h> 27 #include <crypto/algapi.h> 28 #include <crypto/b128ops.h> 29 #include <crypto/hash.h> 30 #include <crypto/kpp.h> 31 32 #include <net/bluetooth/bluetooth.h> 33 #include <net/bluetooth/hci_core.h> 34 #include <net/bluetooth/l2cap.h> 35 #include <net/bluetooth/mgmt.h> 36 37 #include "ecdh_helper.h" 38 #include "smp.h" 39 40 #define SMP_DEV(hdev) \ 41 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data) 42 43 /* Low-level debug macros to be used for stuff that we don't want 44 * accidentially in dmesg, i.e. the values of the various crypto keys 45 * and the inputs & outputs of crypto functions. 46 */ 47 #ifdef DEBUG 48 #define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \ 49 ##__VA_ARGS__) 50 #else 51 #define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \ 52 ##__VA_ARGS__) 53 #endif 54 55 #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) 56 57 /* Keys which are not distributed with Secure Connections */ 58 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY); 59 60 #define SMP_TIMEOUT msecs_to_jiffies(30000) 61 62 #define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \ 63 0x3f : 0x07) 64 #define KEY_DIST_MASK 0x07 65 66 /* Maximum message length that can be passed to aes_cmac */ 67 #define CMAC_MSG_MAX 80 68 69 enum { 70 SMP_FLAG_TK_VALID, 71 SMP_FLAG_CFM_PENDING, 72 SMP_FLAG_MITM_AUTH, 73 SMP_FLAG_COMPLETE, 74 SMP_FLAG_INITIATOR, 75 SMP_FLAG_SC, 76 SMP_FLAG_REMOTE_PK, 77 SMP_FLAG_DEBUG_KEY, 78 SMP_FLAG_WAIT_USER, 79 SMP_FLAG_DHKEY_PENDING, 80 SMP_FLAG_REMOTE_OOB, 81 SMP_FLAG_LOCAL_OOB, 82 SMP_FLAG_CT2, 83 }; 84 85 struct smp_dev { 86 /* Secure Connections OOB data */ 87 bool local_oob; 88 u8 local_pk[64]; 89 u8 local_rand[16]; 90 bool debug_key; 91 92 struct crypto_shash *tfm_cmac; 93 struct crypto_kpp *tfm_ecdh; 94 }; 95 96 struct smp_chan { 97 struct l2cap_conn *conn; 98 struct delayed_work security_timer; 99 unsigned long allow_cmd; /* Bitmask of allowed commands */ 100 101 u8 preq[7]; /* SMP Pairing Request */ 102 u8 prsp[7]; /* SMP Pairing Response */ 103 u8 prnd[16]; /* SMP Pairing Random (local) */ 104 u8 rrnd[16]; /* SMP Pairing Random (remote) */ 105 u8 pcnf[16]; /* SMP Pairing Confirm */ 106 u8 tk[16]; /* SMP Temporary Key */ 107 u8 rr[16]; /* Remote OOB ra/rb value */ 108 u8 lr[16]; /* Local OOB ra/rb value */ 109 u8 enc_key_size; 110 u8 remote_key_dist; 111 bdaddr_t id_addr; 112 u8 id_addr_type; 113 u8 irk[16]; 114 struct smp_csrk *csrk; 115 struct smp_csrk *slave_csrk; 116 struct smp_ltk *ltk; 117 struct smp_ltk *slave_ltk; 118 struct smp_irk *remote_irk; 119 u8 *link_key; 120 unsigned long flags; 121 u8 method; 122 u8 passkey_round; 123 124 /* Secure Connections variables */ 125 u8 local_pk[64]; 126 u8 remote_pk[64]; 127 u8 dhkey[32]; 128 u8 mackey[16]; 129 130 struct crypto_shash *tfm_cmac; 131 struct crypto_kpp *tfm_ecdh; 132 }; 133 134 /* These debug key values are defined in the SMP section of the core 135 * specification. debug_pk is the public debug key and debug_sk the 136 * private debug key. 137 */ 138 static const u8 debug_pk[64] = { 139 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 140 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 141 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 142 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20, 143 144 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74, 145 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76, 146 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63, 147 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc, 148 }; 149 150 static const u8 debug_sk[32] = { 151 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58, 152 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a, 153 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74, 154 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f, 155 }; 156 157 static inline void swap_buf(const u8 *src, u8 *dst, size_t len) 158 { 159 size_t i; 160 161 for (i = 0; i < len; i++) 162 dst[len - 1 - i] = src[i]; 163 } 164 165 /* The following functions map to the LE SC SMP crypto functions 166 * AES-CMAC, f4, f5, f6, g2 and h6. 167 */ 168 169 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, 170 size_t len, u8 mac[16]) 171 { 172 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; 173 SHASH_DESC_ON_STACK(desc, tfm); 174 int err; 175 176 if (len > CMAC_MSG_MAX) 177 return -EFBIG; 178 179 if (!tfm) { 180 BT_ERR("tfm %p", tfm); 181 return -EINVAL; 182 } 183 184 desc->tfm = tfm; 185 186 /* Swap key and message from LSB to MSB */ 187 swap_buf(k, tmp, 16); 188 swap_buf(m, msg_msb, len); 189 190 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m); 191 SMP_DBG("key %16phN", k); 192 193 err = crypto_shash_setkey(tfm, tmp, 16); 194 if (err) { 195 BT_ERR("cipher setkey failed: %d", err); 196 return err; 197 } 198 199 err = crypto_shash_digest(desc, msg_msb, len, mac_msb); 200 shash_desc_zero(desc); 201 if (err) { 202 BT_ERR("Hash computation error %d", err); 203 return err; 204 } 205 206 swap_buf(mac_msb, mac, 16); 207 208 SMP_DBG("mac %16phN", mac); 209 210 return 0; 211 } 212 213 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32], 214 const u8 v[32], const u8 x[16], u8 z, u8 res[16]) 215 { 216 u8 m[65]; 217 int err; 218 219 SMP_DBG("u %32phN", u); 220 SMP_DBG("v %32phN", v); 221 SMP_DBG("x %16phN z %02x", x, z); 222 223 m[0] = z; 224 memcpy(m + 1, v, 32); 225 memcpy(m + 33, u, 32); 226 227 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); 228 if (err) 229 return err; 230 231 SMP_DBG("res %16phN", res); 232 233 return err; 234 } 235 236 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32], 237 const u8 n1[16], const u8 n2[16], const u8 a1[7], 238 const u8 a2[7], u8 mackey[16], u8 ltk[16]) 239 { 240 /* The btle, salt and length "magic" values are as defined in 241 * the SMP section of the Bluetooth core specification. In ASCII 242 * the btle value ends up being 'btle'. The salt is just a 243 * random number whereas length is the value 256 in little 244 * endian format. 245 */ 246 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; 247 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, 248 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; 249 const u8 length[2] = { 0x00, 0x01 }; 250 u8 m[53], t[16]; 251 int err; 252 253 SMP_DBG("w %32phN", w); 254 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 255 SMP_DBG("a1 %7phN a2 %7phN", a1, a2); 256 257 err = aes_cmac(tfm_cmac, salt, w, 32, t); 258 if (err) 259 return err; 260 261 SMP_DBG("t %16phN", t); 262 263 memcpy(m, length, 2); 264 memcpy(m + 2, a2, 7); 265 memcpy(m + 9, a1, 7); 266 memcpy(m + 16, n2, 16); 267 memcpy(m + 32, n1, 16); 268 memcpy(m + 48, btle, 4); 269 270 m[52] = 0; /* Counter */ 271 272 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); 273 if (err) 274 return err; 275 276 SMP_DBG("mackey %16phN", mackey); 277 278 m[52] = 1; /* Counter */ 279 280 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); 281 if (err) 282 return err; 283 284 SMP_DBG("ltk %16phN", ltk); 285 286 return 0; 287 } 288 289 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16], 290 const u8 n1[16], const u8 n2[16], const u8 r[16], 291 const u8 io_cap[3], const u8 a1[7], const u8 a2[7], 292 u8 res[16]) 293 { 294 u8 m[65]; 295 int err; 296 297 SMP_DBG("w %16phN", w); 298 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 299 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); 300 301 memcpy(m, a2, 7); 302 memcpy(m + 7, a1, 7); 303 memcpy(m + 14, io_cap, 3); 304 memcpy(m + 17, r, 16); 305 memcpy(m + 33, n2, 16); 306 memcpy(m + 49, n1, 16); 307 308 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); 309 if (err) 310 return err; 311 312 SMP_DBG("res %16phN", res); 313 314 return err; 315 } 316 317 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32], 318 const u8 x[16], const u8 y[16], u32 *val) 319 { 320 u8 m[80], tmp[16]; 321 int err; 322 323 SMP_DBG("u %32phN", u); 324 SMP_DBG("v %32phN", v); 325 SMP_DBG("x %16phN y %16phN", x, y); 326 327 memcpy(m, y, 16); 328 memcpy(m + 16, v, 32); 329 memcpy(m + 48, u, 32); 330 331 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); 332 if (err) 333 return err; 334 335 *val = get_unaligned_le32(tmp); 336 *val %= 1000000; 337 338 SMP_DBG("val %06u", *val); 339 340 return 0; 341 } 342 343 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], 344 const u8 key_id[4], u8 res[16]) 345 { 346 int err; 347 348 SMP_DBG("w %16phN key_id %4phN", w, key_id); 349 350 err = aes_cmac(tfm_cmac, w, key_id, 4, res); 351 if (err) 352 return err; 353 354 SMP_DBG("res %16phN", res); 355 356 return err; 357 } 358 359 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16], 360 const u8 salt[16], u8 res[16]) 361 { 362 int err; 363 364 SMP_DBG("w %16phN salt %16phN", w, salt); 365 366 err = aes_cmac(tfm_cmac, salt, w, 16, res); 367 if (err) 368 return err; 369 370 SMP_DBG("res %16phN", res); 371 372 return err; 373 } 374 375 /* The following functions map to the legacy SMP crypto functions e, c1, 376 * s1 and ah. 377 */ 378 379 static int smp_e(const u8 *k, u8 *r) 380 { 381 struct crypto_aes_ctx ctx; 382 uint8_t tmp[16], data[16]; 383 int err; 384 385 SMP_DBG("k %16phN r %16phN", k, r); 386 387 /* The most significant octet of key corresponds to k[0] */ 388 swap_buf(k, tmp, 16); 389 390 err = aes_expandkey(&ctx, tmp, 16); 391 if (err) { 392 BT_ERR("cipher setkey failed: %d", err); 393 return err; 394 } 395 396 /* Most significant octet of plaintextData corresponds to data[0] */ 397 swap_buf(r, data, 16); 398 399 aes_encrypt(&ctx, data, data); 400 401 /* Most significant octet of encryptedData corresponds to data[0] */ 402 swap_buf(data, r, 16); 403 404 SMP_DBG("r %16phN", r); 405 406 memzero_explicit(&ctx, sizeof (ctx)); 407 return err; 408 } 409 410 static int smp_c1(const u8 k[16], 411 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat, 412 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16]) 413 { 414 u8 p1[16], p2[16]; 415 int err; 416 417 SMP_DBG("k %16phN r %16phN", k, r); 418 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra); 419 SMP_DBG("preq %7phN pres %7phN", preq, pres); 420 421 memset(p1, 0, 16); 422 423 /* p1 = pres || preq || _rat || _iat */ 424 p1[0] = _iat; 425 p1[1] = _rat; 426 memcpy(p1 + 2, preq, 7); 427 memcpy(p1 + 9, pres, 7); 428 429 SMP_DBG("p1 %16phN", p1); 430 431 /* res = r XOR p1 */ 432 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); 433 434 /* res = e(k, res) */ 435 err = smp_e(k, res); 436 if (err) { 437 BT_ERR("Encrypt data error"); 438 return err; 439 } 440 441 /* p2 = padding || ia || ra */ 442 memcpy(p2, ra, 6); 443 memcpy(p2 + 6, ia, 6); 444 memset(p2 + 12, 0, 4); 445 446 SMP_DBG("p2 %16phN", p2); 447 448 /* res = res XOR p2 */ 449 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); 450 451 /* res = e(k, res) */ 452 err = smp_e(k, res); 453 if (err) 454 BT_ERR("Encrypt data error"); 455 456 return err; 457 } 458 459 static int smp_s1(const u8 k[16], 460 const u8 r1[16], const u8 r2[16], u8 _r[16]) 461 { 462 int err; 463 464 /* Just least significant octets from r1 and r2 are considered */ 465 memcpy(_r, r2, 8); 466 memcpy(_r + 8, r1, 8); 467 468 err = smp_e(k, _r); 469 if (err) 470 BT_ERR("Encrypt data error"); 471 472 return err; 473 } 474 475 static int smp_ah(const u8 irk[16], const u8 r[3], u8 res[3]) 476 { 477 u8 _res[16]; 478 int err; 479 480 /* r' = padding || r */ 481 memcpy(_res, r, 3); 482 memset(_res + 3, 0, 13); 483 484 err = smp_e(irk, _res); 485 if (err) { 486 BT_ERR("Encrypt error"); 487 return err; 488 } 489 490 /* The output of the random address function ah is: 491 * ah(k, r) = e(k, r') mod 2^24 492 * The output of the security function e is then truncated to 24 bits 493 * by taking the least significant 24 bits of the output of e as the 494 * result of ah. 495 */ 496 memcpy(res, _res, 3); 497 498 return 0; 499 } 500 501 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 502 const bdaddr_t *bdaddr) 503 { 504 struct l2cap_chan *chan = hdev->smp_data; 505 u8 hash[3]; 506 int err; 507 508 if (!chan || !chan->data) 509 return false; 510 511 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk); 512 513 err = smp_ah(irk, &bdaddr->b[3], hash); 514 if (err) 515 return false; 516 517 return !crypto_memneq(bdaddr->b, hash, 3); 518 } 519 520 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa) 521 { 522 struct l2cap_chan *chan = hdev->smp_data; 523 int err; 524 525 if (!chan || !chan->data) 526 return -EOPNOTSUPP; 527 528 get_random_bytes(&rpa->b[3], 3); 529 530 rpa->b[5] &= 0x3f; /* Clear two most significant bits */ 531 rpa->b[5] |= 0x40; /* Set second most significant bit */ 532 533 err = smp_ah(irk, &rpa->b[3], rpa->b); 534 if (err < 0) 535 return err; 536 537 BT_DBG("RPA %pMR", rpa); 538 539 return 0; 540 } 541 542 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16]) 543 { 544 struct l2cap_chan *chan = hdev->smp_data; 545 struct smp_dev *smp; 546 int err; 547 548 if (!chan || !chan->data) 549 return -EOPNOTSUPP; 550 551 smp = chan->data; 552 553 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 554 BT_DBG("Using debug keys"); 555 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk); 556 if (err) 557 return err; 558 memcpy(smp->local_pk, debug_pk, 64); 559 smp->debug_key = true; 560 } else { 561 while (true) { 562 /* Generate key pair for Secure Connections */ 563 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk); 564 if (err) 565 return err; 566 567 /* This is unlikely, but we need to check that 568 * we didn't accidentially generate a debug key. 569 */ 570 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 571 break; 572 } 573 smp->debug_key = false; 574 } 575 576 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk); 577 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32); 578 579 get_random_bytes(smp->local_rand, 16); 580 581 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk, 582 smp->local_rand, 0, hash); 583 if (err < 0) 584 return err; 585 586 memcpy(rand, smp->local_rand, 16); 587 588 smp->local_oob = true; 589 590 return 0; 591 } 592 593 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) 594 { 595 struct l2cap_chan *chan = conn->smp; 596 struct smp_chan *smp; 597 struct kvec iv[2]; 598 struct msghdr msg; 599 600 if (!chan) 601 return; 602 603 BT_DBG("code 0x%2.2x", code); 604 605 iv[0].iov_base = &code; 606 iv[0].iov_len = 1; 607 608 iv[1].iov_base = data; 609 iv[1].iov_len = len; 610 611 memset(&msg, 0, sizeof(msg)); 612 613 iov_iter_kvec(&msg.msg_iter, WRITE, iv, 2, 1 + len); 614 615 l2cap_chan_send(chan, &msg, 1 + len); 616 617 if (!chan->data) 618 return; 619 620 smp = chan->data; 621 622 cancel_delayed_work_sync(&smp->security_timer); 623 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); 624 } 625 626 static u8 authreq_to_seclevel(u8 authreq) 627 { 628 if (authreq & SMP_AUTH_MITM) { 629 if (authreq & SMP_AUTH_SC) 630 return BT_SECURITY_FIPS; 631 else 632 return BT_SECURITY_HIGH; 633 } else { 634 return BT_SECURITY_MEDIUM; 635 } 636 } 637 638 static __u8 seclevel_to_authreq(__u8 sec_level) 639 { 640 switch (sec_level) { 641 case BT_SECURITY_FIPS: 642 case BT_SECURITY_HIGH: 643 return SMP_AUTH_MITM | SMP_AUTH_BONDING; 644 case BT_SECURITY_MEDIUM: 645 return SMP_AUTH_BONDING; 646 default: 647 return SMP_AUTH_NONE; 648 } 649 } 650 651 static void build_pairing_cmd(struct l2cap_conn *conn, 652 struct smp_cmd_pairing *req, 653 struct smp_cmd_pairing *rsp, __u8 authreq) 654 { 655 struct l2cap_chan *chan = conn->smp; 656 struct smp_chan *smp = chan->data; 657 struct hci_conn *hcon = conn->hcon; 658 struct hci_dev *hdev = hcon->hdev; 659 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT; 660 661 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 662 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 663 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 664 authreq |= SMP_AUTH_BONDING; 665 } else { 666 authreq &= ~SMP_AUTH_BONDING; 667 } 668 669 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 670 remote_dist |= SMP_DIST_ID_KEY; 671 672 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 673 local_dist |= SMP_DIST_ID_KEY; 674 675 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) && 676 (authreq & SMP_AUTH_SC)) { 677 struct oob_data *oob_data; 678 u8 bdaddr_type; 679 680 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) { 681 local_dist |= SMP_DIST_LINK_KEY; 682 remote_dist |= SMP_DIST_LINK_KEY; 683 } 684 685 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC) 686 bdaddr_type = BDADDR_LE_PUBLIC; 687 else 688 bdaddr_type = BDADDR_LE_RANDOM; 689 690 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst, 691 bdaddr_type); 692 if (oob_data && oob_data->present) { 693 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags); 694 oob_flag = SMP_OOB_PRESENT; 695 memcpy(smp->rr, oob_data->rand256, 16); 696 memcpy(smp->pcnf, oob_data->hash256, 16); 697 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf); 698 SMP_DBG("OOB Remote Random: %16phN", smp->rr); 699 } 700 701 } else { 702 authreq &= ~SMP_AUTH_SC; 703 } 704 705 if (rsp == NULL) { 706 req->io_capability = conn->hcon->io_capability; 707 req->oob_flag = oob_flag; 708 req->max_key_size = hdev->le_max_key_size; 709 req->init_key_dist = local_dist; 710 req->resp_key_dist = remote_dist; 711 req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 712 713 smp->remote_key_dist = remote_dist; 714 return; 715 } 716 717 rsp->io_capability = conn->hcon->io_capability; 718 rsp->oob_flag = oob_flag; 719 rsp->max_key_size = hdev->le_max_key_size; 720 rsp->init_key_dist = req->init_key_dist & remote_dist; 721 rsp->resp_key_dist = req->resp_key_dist & local_dist; 722 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 723 724 smp->remote_key_dist = rsp->init_key_dist; 725 } 726 727 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) 728 { 729 struct l2cap_chan *chan = conn->smp; 730 struct hci_dev *hdev = conn->hcon->hdev; 731 struct smp_chan *smp = chan->data; 732 733 if (max_key_size > hdev->le_max_key_size || 734 max_key_size < SMP_MIN_ENC_KEY_SIZE) 735 return SMP_ENC_KEY_SIZE; 736 737 smp->enc_key_size = max_key_size; 738 739 return 0; 740 } 741 742 static void smp_chan_destroy(struct l2cap_conn *conn) 743 { 744 struct l2cap_chan *chan = conn->smp; 745 struct smp_chan *smp = chan->data; 746 struct hci_conn *hcon = conn->hcon; 747 bool complete; 748 749 BUG_ON(!smp); 750 751 cancel_delayed_work_sync(&smp->security_timer); 752 753 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); 754 mgmt_smp_complete(hcon, complete); 755 756 kzfree(smp->csrk); 757 kzfree(smp->slave_csrk); 758 kzfree(smp->link_key); 759 760 crypto_free_shash(smp->tfm_cmac); 761 crypto_free_kpp(smp->tfm_ecdh); 762 763 /* Ensure that we don't leave any debug key around if debug key 764 * support hasn't been explicitly enabled. 765 */ 766 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG && 767 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) { 768 list_del_rcu(&smp->ltk->list); 769 kfree_rcu(smp->ltk, rcu); 770 smp->ltk = NULL; 771 } 772 773 /* If pairing failed clean up any keys we might have */ 774 if (!complete) { 775 if (smp->ltk) { 776 list_del_rcu(&smp->ltk->list); 777 kfree_rcu(smp->ltk, rcu); 778 } 779 780 if (smp->slave_ltk) { 781 list_del_rcu(&smp->slave_ltk->list); 782 kfree_rcu(smp->slave_ltk, rcu); 783 } 784 785 if (smp->remote_irk) { 786 list_del_rcu(&smp->remote_irk->list); 787 kfree_rcu(smp->remote_irk, rcu); 788 } 789 } 790 791 chan->data = NULL; 792 kzfree(smp); 793 hci_conn_drop(hcon); 794 } 795 796 static void smp_failure(struct l2cap_conn *conn, u8 reason) 797 { 798 struct hci_conn *hcon = conn->hcon; 799 struct l2cap_chan *chan = conn->smp; 800 801 if (reason) 802 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), 803 &reason); 804 805 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); 806 807 if (chan->data) 808 smp_chan_destroy(conn); 809 } 810 811 #define JUST_WORKS 0x00 812 #define JUST_CFM 0x01 813 #define REQ_PASSKEY 0x02 814 #define CFM_PASSKEY 0x03 815 #define REQ_OOB 0x04 816 #define DSP_PASSKEY 0x05 817 #define OVERLAP 0xFF 818 819 static const u8 gen_method[5][5] = { 820 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 821 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 822 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 823 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 824 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, 825 }; 826 827 static const u8 sc_method[5][5] = { 828 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 829 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 830 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY }, 831 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 832 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 833 }; 834 835 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) 836 { 837 /* If either side has unknown io_caps, use JUST_CFM (which gets 838 * converted later to JUST_WORKS if we're initiators. 839 */ 840 if (local_io > SMP_IO_KEYBOARD_DISPLAY || 841 remote_io > SMP_IO_KEYBOARD_DISPLAY) 842 return JUST_CFM; 843 844 if (test_bit(SMP_FLAG_SC, &smp->flags)) 845 return sc_method[remote_io][local_io]; 846 847 return gen_method[remote_io][local_io]; 848 } 849 850 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, 851 u8 local_io, u8 remote_io) 852 { 853 struct hci_conn *hcon = conn->hcon; 854 struct l2cap_chan *chan = conn->smp; 855 struct smp_chan *smp = chan->data; 856 u32 passkey = 0; 857 int ret = 0; 858 859 /* Initialize key for JUST WORKS */ 860 memset(smp->tk, 0, sizeof(smp->tk)); 861 clear_bit(SMP_FLAG_TK_VALID, &smp->flags); 862 863 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io); 864 865 /* If neither side wants MITM, either "just" confirm an incoming 866 * request or use just-works for outgoing ones. The JUST_CFM 867 * will be converted to JUST_WORKS if necessary later in this 868 * function. If either side has MITM look up the method from the 869 * table. 870 */ 871 if (!(auth & SMP_AUTH_MITM)) 872 smp->method = JUST_CFM; 873 else 874 smp->method = get_auth_method(smp, local_io, remote_io); 875 876 /* Don't confirm locally initiated pairing attempts */ 877 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, 878 &smp->flags)) 879 smp->method = JUST_WORKS; 880 881 /* Don't bother user space with no IO capabilities */ 882 if (smp->method == JUST_CFM && 883 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 884 smp->method = JUST_WORKS; 885 886 /* If Just Works, Continue with Zero TK */ 887 if (smp->method == JUST_WORKS) { 888 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 889 return 0; 890 } 891 892 /* If this function is used for SC -> legacy fallback we 893 * can only recover the just-works case. 894 */ 895 if (test_bit(SMP_FLAG_SC, &smp->flags)) 896 return -EINVAL; 897 898 /* Not Just Works/Confirm results in MITM Authentication */ 899 if (smp->method != JUST_CFM) { 900 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags); 901 if (hcon->pending_sec_level < BT_SECURITY_HIGH) 902 hcon->pending_sec_level = BT_SECURITY_HIGH; 903 } 904 905 /* If both devices have Keyoard-Display I/O, the master 906 * Confirms and the slave Enters the passkey. 907 */ 908 if (smp->method == OVERLAP) { 909 if (hcon->role == HCI_ROLE_MASTER) 910 smp->method = CFM_PASSKEY; 911 else 912 smp->method = REQ_PASSKEY; 913 } 914 915 /* Generate random passkey. */ 916 if (smp->method == CFM_PASSKEY) { 917 memset(smp->tk, 0, sizeof(smp->tk)); 918 get_random_bytes(&passkey, sizeof(passkey)); 919 passkey %= 1000000; 920 put_unaligned_le32(passkey, smp->tk); 921 BT_DBG("PassKey: %d", passkey); 922 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 923 } 924 925 if (smp->method == REQ_PASSKEY) 926 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst, 927 hcon->type, hcon->dst_type); 928 else if (smp->method == JUST_CFM) 929 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 930 hcon->type, hcon->dst_type, 931 passkey, 1); 932 else 933 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst, 934 hcon->type, hcon->dst_type, 935 passkey, 0); 936 937 return ret; 938 } 939 940 static u8 smp_confirm(struct smp_chan *smp) 941 { 942 struct l2cap_conn *conn = smp->conn; 943 struct smp_cmd_pairing_confirm cp; 944 int ret; 945 946 BT_DBG("conn %p", conn); 947 948 ret = smp_c1(smp->tk, smp->prnd, smp->preq, smp->prsp, 949 conn->hcon->init_addr_type, &conn->hcon->init_addr, 950 conn->hcon->resp_addr_type, &conn->hcon->resp_addr, 951 cp.confirm_val); 952 if (ret) 953 return SMP_UNSPECIFIED; 954 955 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 956 957 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); 958 959 if (conn->hcon->out) 960 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 961 else 962 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 963 964 return 0; 965 } 966 967 static u8 smp_random(struct smp_chan *smp) 968 { 969 struct l2cap_conn *conn = smp->conn; 970 struct hci_conn *hcon = conn->hcon; 971 u8 confirm[16]; 972 int ret; 973 974 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 975 976 ret = smp_c1(smp->tk, smp->rrnd, smp->preq, smp->prsp, 977 hcon->init_addr_type, &hcon->init_addr, 978 hcon->resp_addr_type, &hcon->resp_addr, confirm); 979 if (ret) 980 return SMP_UNSPECIFIED; 981 982 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) { 983 bt_dev_err(hcon->hdev, "pairing failed " 984 "(confirmation values mismatch)"); 985 return SMP_CONFIRM_FAILED; 986 } 987 988 if (hcon->out) { 989 u8 stk[16]; 990 __le64 rand = 0; 991 __le16 ediv = 0; 992 993 smp_s1(smp->tk, smp->rrnd, smp->prnd, stk); 994 995 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 996 return SMP_UNSPECIFIED; 997 998 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size); 999 hcon->enc_key_size = smp->enc_key_size; 1000 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 1001 } else { 1002 u8 stk[16], auth; 1003 __le64 rand = 0; 1004 __le16 ediv = 0; 1005 1006 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 1007 smp->prnd); 1008 1009 smp_s1(smp->tk, smp->prnd, smp->rrnd, stk); 1010 1011 if (hcon->pending_sec_level == BT_SECURITY_HIGH) 1012 auth = 1; 1013 else 1014 auth = 0; 1015 1016 /* Even though there's no _SLAVE suffix this is the 1017 * slave STK we're adding for later lookup (the master 1018 * STK never needs to be stored). 1019 */ 1020 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1021 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); 1022 } 1023 1024 return 0; 1025 } 1026 1027 static void smp_notify_keys(struct l2cap_conn *conn) 1028 { 1029 struct l2cap_chan *chan = conn->smp; 1030 struct smp_chan *smp = chan->data; 1031 struct hci_conn *hcon = conn->hcon; 1032 struct hci_dev *hdev = hcon->hdev; 1033 struct smp_cmd_pairing *req = (void *) &smp->preq[1]; 1034 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; 1035 bool persistent; 1036 1037 if (hcon->type == ACL_LINK) { 1038 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) 1039 persistent = false; 1040 else 1041 persistent = !test_bit(HCI_CONN_FLUSH_KEY, 1042 &hcon->flags); 1043 } else { 1044 /* The LTKs, IRKs and CSRKs should be persistent only if 1045 * both sides had the bonding bit set in their 1046 * authentication requests. 1047 */ 1048 persistent = !!((req->auth_req & rsp->auth_req) & 1049 SMP_AUTH_BONDING); 1050 } 1051 1052 if (smp->remote_irk) { 1053 mgmt_new_irk(hdev, smp->remote_irk, persistent); 1054 1055 /* Now that user space can be considered to know the 1056 * identity address track the connection based on it 1057 * from now on (assuming this is an LE link). 1058 */ 1059 if (hcon->type == LE_LINK) { 1060 bacpy(&hcon->dst, &smp->remote_irk->bdaddr); 1061 hcon->dst_type = smp->remote_irk->addr_type; 1062 queue_work(hdev->workqueue, &conn->id_addr_update_work); 1063 } 1064 } 1065 1066 if (smp->csrk) { 1067 smp->csrk->bdaddr_type = hcon->dst_type; 1068 bacpy(&smp->csrk->bdaddr, &hcon->dst); 1069 mgmt_new_csrk(hdev, smp->csrk, persistent); 1070 } 1071 1072 if (smp->slave_csrk) { 1073 smp->slave_csrk->bdaddr_type = hcon->dst_type; 1074 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); 1075 mgmt_new_csrk(hdev, smp->slave_csrk, persistent); 1076 } 1077 1078 if (smp->ltk) { 1079 smp->ltk->bdaddr_type = hcon->dst_type; 1080 bacpy(&smp->ltk->bdaddr, &hcon->dst); 1081 mgmt_new_ltk(hdev, smp->ltk, persistent); 1082 } 1083 1084 if (smp->slave_ltk) { 1085 smp->slave_ltk->bdaddr_type = hcon->dst_type; 1086 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); 1087 mgmt_new_ltk(hdev, smp->slave_ltk, persistent); 1088 } 1089 1090 if (smp->link_key) { 1091 struct link_key *key; 1092 u8 type; 1093 1094 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1095 type = HCI_LK_DEBUG_COMBINATION; 1096 else if (hcon->sec_level == BT_SECURITY_FIPS) 1097 type = HCI_LK_AUTH_COMBINATION_P256; 1098 else 1099 type = HCI_LK_UNAUTH_COMBINATION_P256; 1100 1101 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst, 1102 smp->link_key, type, 0, &persistent); 1103 if (key) { 1104 mgmt_new_link_key(hdev, key, persistent); 1105 1106 /* Don't keep debug keys around if the relevant 1107 * flag is not set. 1108 */ 1109 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) && 1110 key->type == HCI_LK_DEBUG_COMBINATION) { 1111 list_del_rcu(&key->list); 1112 kfree_rcu(key, rcu); 1113 } 1114 } 1115 } 1116 } 1117 1118 static void sc_add_ltk(struct smp_chan *smp) 1119 { 1120 struct hci_conn *hcon = smp->conn->hcon; 1121 u8 key_type, auth; 1122 1123 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1124 key_type = SMP_LTK_P256_DEBUG; 1125 else 1126 key_type = SMP_LTK_P256; 1127 1128 if (hcon->pending_sec_level == BT_SECURITY_FIPS) 1129 auth = 1; 1130 else 1131 auth = 0; 1132 1133 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1134 key_type, auth, smp->tk, smp->enc_key_size, 1135 0, 0); 1136 } 1137 1138 static void sc_generate_link_key(struct smp_chan *smp) 1139 { 1140 /* From core spec. Spells out in ASCII as 'lebr'. */ 1141 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c }; 1142 1143 smp->link_key = kzalloc(16, GFP_KERNEL); 1144 if (!smp->link_key) 1145 return; 1146 1147 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1148 /* SALT = 0x00000000000000000000000000000000746D7031 */ 1149 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 }; 1150 1151 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) { 1152 kzfree(smp->link_key); 1153 smp->link_key = NULL; 1154 return; 1155 } 1156 } else { 1157 /* From core spec. Spells out in ASCII as 'tmp1'. */ 1158 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 }; 1159 1160 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) { 1161 kzfree(smp->link_key); 1162 smp->link_key = NULL; 1163 return; 1164 } 1165 } 1166 1167 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) { 1168 kzfree(smp->link_key); 1169 smp->link_key = NULL; 1170 return; 1171 } 1172 } 1173 1174 static void smp_allow_key_dist(struct smp_chan *smp) 1175 { 1176 /* Allow the first expected phase 3 PDU. The rest of the PDUs 1177 * will be allowed in each PDU handler to ensure we receive 1178 * them in the correct order. 1179 */ 1180 if (smp->remote_key_dist & SMP_DIST_ENC_KEY) 1181 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); 1182 else if (smp->remote_key_dist & SMP_DIST_ID_KEY) 1183 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 1184 else if (smp->remote_key_dist & SMP_DIST_SIGN) 1185 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 1186 } 1187 1188 static void sc_generate_ltk(struct smp_chan *smp) 1189 { 1190 /* From core spec. Spells out in ASCII as 'brle'. */ 1191 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 }; 1192 struct hci_conn *hcon = smp->conn->hcon; 1193 struct hci_dev *hdev = hcon->hdev; 1194 struct link_key *key; 1195 1196 key = hci_find_link_key(hdev, &hcon->dst); 1197 if (!key) { 1198 bt_dev_err(hdev, "no Link Key found to generate LTK"); 1199 return; 1200 } 1201 1202 if (key->type == HCI_LK_DEBUG_COMBINATION) 1203 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1204 1205 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1206 /* SALT = 0x00000000000000000000000000000000746D7032 */ 1207 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 }; 1208 1209 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk)) 1210 return; 1211 } else { 1212 /* From core spec. Spells out in ASCII as 'tmp2'. */ 1213 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 }; 1214 1215 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk)) 1216 return; 1217 } 1218 1219 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk)) 1220 return; 1221 1222 sc_add_ltk(smp); 1223 } 1224 1225 static void smp_distribute_keys(struct smp_chan *smp) 1226 { 1227 struct smp_cmd_pairing *req, *rsp; 1228 struct l2cap_conn *conn = smp->conn; 1229 struct hci_conn *hcon = conn->hcon; 1230 struct hci_dev *hdev = hcon->hdev; 1231 __u8 *keydist; 1232 1233 BT_DBG("conn %p", conn); 1234 1235 rsp = (void *) &smp->prsp[1]; 1236 1237 /* The responder sends its keys first */ 1238 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { 1239 smp_allow_key_dist(smp); 1240 return; 1241 } 1242 1243 req = (void *) &smp->preq[1]; 1244 1245 if (hcon->out) { 1246 keydist = &rsp->init_key_dist; 1247 *keydist &= req->init_key_dist; 1248 } else { 1249 keydist = &rsp->resp_key_dist; 1250 *keydist &= req->resp_key_dist; 1251 } 1252 1253 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1254 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY)) 1255 sc_generate_link_key(smp); 1256 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY)) 1257 sc_generate_ltk(smp); 1258 1259 /* Clear the keys which are generated but not distributed */ 1260 *keydist &= ~SMP_SC_NO_DIST; 1261 } 1262 1263 BT_DBG("keydist 0x%x", *keydist); 1264 1265 if (*keydist & SMP_DIST_ENC_KEY) { 1266 struct smp_cmd_encrypt_info enc; 1267 struct smp_cmd_master_ident ident; 1268 struct smp_ltk *ltk; 1269 u8 authenticated; 1270 __le16 ediv; 1271 __le64 rand; 1272 1273 /* Make sure we generate only the significant amount of 1274 * bytes based on the encryption key size, and set the rest 1275 * of the value to zeroes. 1276 */ 1277 get_random_bytes(enc.ltk, smp->enc_key_size); 1278 memset(enc.ltk + smp->enc_key_size, 0, 1279 sizeof(enc.ltk) - smp->enc_key_size); 1280 1281 get_random_bytes(&ediv, sizeof(ediv)); 1282 get_random_bytes(&rand, sizeof(rand)); 1283 1284 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); 1285 1286 authenticated = hcon->sec_level == BT_SECURITY_HIGH; 1287 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, 1288 SMP_LTK_SLAVE, authenticated, enc.ltk, 1289 smp->enc_key_size, ediv, rand); 1290 smp->slave_ltk = ltk; 1291 1292 ident.ediv = ediv; 1293 ident.rand = rand; 1294 1295 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); 1296 1297 *keydist &= ~SMP_DIST_ENC_KEY; 1298 } 1299 1300 if (*keydist & SMP_DIST_ID_KEY) { 1301 struct smp_cmd_ident_addr_info addrinfo; 1302 struct smp_cmd_ident_info idinfo; 1303 1304 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); 1305 1306 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); 1307 1308 /* The hci_conn contains the local identity address 1309 * after the connection has been established. 1310 * 1311 * This is true even when the connection has been 1312 * established using a resolvable random address. 1313 */ 1314 bacpy(&addrinfo.bdaddr, &hcon->src); 1315 addrinfo.addr_type = hcon->src_type; 1316 1317 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), 1318 &addrinfo); 1319 1320 *keydist &= ~SMP_DIST_ID_KEY; 1321 } 1322 1323 if (*keydist & SMP_DIST_SIGN) { 1324 struct smp_cmd_sign_info sign; 1325 struct smp_csrk *csrk; 1326 1327 /* Generate a new random key */ 1328 get_random_bytes(sign.csrk, sizeof(sign.csrk)); 1329 1330 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 1331 if (csrk) { 1332 if (hcon->sec_level > BT_SECURITY_MEDIUM) 1333 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED; 1334 else 1335 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED; 1336 memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); 1337 } 1338 smp->slave_csrk = csrk; 1339 1340 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); 1341 1342 *keydist &= ~SMP_DIST_SIGN; 1343 } 1344 1345 /* If there are still keys to be received wait for them */ 1346 if (smp->remote_key_dist & KEY_DIST_MASK) { 1347 smp_allow_key_dist(smp); 1348 return; 1349 } 1350 1351 set_bit(SMP_FLAG_COMPLETE, &smp->flags); 1352 smp_notify_keys(conn); 1353 1354 smp_chan_destroy(conn); 1355 } 1356 1357 static void smp_timeout(struct work_struct *work) 1358 { 1359 struct smp_chan *smp = container_of(work, struct smp_chan, 1360 security_timer.work); 1361 struct l2cap_conn *conn = smp->conn; 1362 1363 BT_DBG("conn %p", conn); 1364 1365 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); 1366 } 1367 1368 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) 1369 { 1370 struct l2cap_chan *chan = conn->smp; 1371 struct smp_chan *smp; 1372 1373 smp = kzalloc(sizeof(*smp), GFP_ATOMIC); 1374 if (!smp) 1375 return NULL; 1376 1377 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 1378 if (IS_ERR(smp->tfm_cmac)) { 1379 BT_ERR("Unable to create CMAC crypto context"); 1380 goto zfree_smp; 1381 } 1382 1383 smp->tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0); 1384 if (IS_ERR(smp->tfm_ecdh)) { 1385 BT_ERR("Unable to create ECDH crypto context"); 1386 goto free_shash; 1387 } 1388 1389 smp->conn = conn; 1390 chan->data = smp; 1391 1392 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); 1393 1394 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); 1395 1396 hci_conn_hold(conn->hcon); 1397 1398 return smp; 1399 1400 free_shash: 1401 crypto_free_shash(smp->tfm_cmac); 1402 zfree_smp: 1403 kzfree(smp); 1404 return NULL; 1405 } 1406 1407 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) 1408 { 1409 struct hci_conn *hcon = smp->conn->hcon; 1410 u8 *na, *nb, a[7], b[7]; 1411 1412 if (hcon->out) { 1413 na = smp->prnd; 1414 nb = smp->rrnd; 1415 } else { 1416 na = smp->rrnd; 1417 nb = smp->prnd; 1418 } 1419 1420 memcpy(a, &hcon->init_addr, 6); 1421 memcpy(b, &hcon->resp_addr, 6); 1422 a[6] = hcon->init_addr_type; 1423 b[6] = hcon->resp_addr_type; 1424 1425 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); 1426 } 1427 1428 static void sc_dhkey_check(struct smp_chan *smp) 1429 { 1430 struct hci_conn *hcon = smp->conn->hcon; 1431 struct smp_cmd_dhkey_check check; 1432 u8 a[7], b[7], *local_addr, *remote_addr; 1433 u8 io_cap[3], r[16]; 1434 1435 memcpy(a, &hcon->init_addr, 6); 1436 memcpy(b, &hcon->resp_addr, 6); 1437 a[6] = hcon->init_addr_type; 1438 b[6] = hcon->resp_addr_type; 1439 1440 if (hcon->out) { 1441 local_addr = a; 1442 remote_addr = b; 1443 memcpy(io_cap, &smp->preq[1], 3); 1444 } else { 1445 local_addr = b; 1446 remote_addr = a; 1447 memcpy(io_cap, &smp->prsp[1], 3); 1448 } 1449 1450 memset(r, 0, sizeof(r)); 1451 1452 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 1453 put_unaligned_le32(hcon->passkey_notify, r); 1454 1455 if (smp->method == REQ_OOB) 1456 memcpy(r, smp->rr, 16); 1457 1458 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, 1459 local_addr, remote_addr, check.e); 1460 1461 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); 1462 } 1463 1464 static u8 sc_passkey_send_confirm(struct smp_chan *smp) 1465 { 1466 struct l2cap_conn *conn = smp->conn; 1467 struct hci_conn *hcon = conn->hcon; 1468 struct smp_cmd_pairing_confirm cfm; 1469 u8 r; 1470 1471 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1472 r |= 0x80; 1473 1474 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1475 1476 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r, 1477 cfm.confirm_val)) 1478 return SMP_UNSPECIFIED; 1479 1480 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 1481 1482 return 0; 1483 } 1484 1485 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op) 1486 { 1487 struct l2cap_conn *conn = smp->conn; 1488 struct hci_conn *hcon = conn->hcon; 1489 struct hci_dev *hdev = hcon->hdev; 1490 u8 cfm[16], r; 1491 1492 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */ 1493 if (smp->passkey_round >= 20) 1494 return 0; 1495 1496 switch (smp_op) { 1497 case SMP_CMD_PAIRING_RANDOM: 1498 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1499 r |= 0x80; 1500 1501 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 1502 smp->rrnd, r, cfm)) 1503 return SMP_UNSPECIFIED; 1504 1505 if (crypto_memneq(smp->pcnf, cfm, 16)) 1506 return SMP_CONFIRM_FAILED; 1507 1508 smp->passkey_round++; 1509 1510 if (smp->passkey_round == 20) { 1511 /* Generate MacKey and LTK */ 1512 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk)) 1513 return SMP_UNSPECIFIED; 1514 } 1515 1516 /* The round is only complete when the initiator 1517 * receives pairing random. 1518 */ 1519 if (!hcon->out) { 1520 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1521 sizeof(smp->prnd), smp->prnd); 1522 if (smp->passkey_round == 20) 1523 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1524 else 1525 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1526 return 0; 1527 } 1528 1529 /* Start the next round */ 1530 if (smp->passkey_round != 20) 1531 return sc_passkey_round(smp, 0); 1532 1533 /* Passkey rounds are complete - start DHKey Check */ 1534 sc_dhkey_check(smp); 1535 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1536 1537 break; 1538 1539 case SMP_CMD_PAIRING_CONFIRM: 1540 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 1541 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 1542 return 0; 1543 } 1544 1545 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 1546 1547 if (hcon->out) { 1548 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1549 sizeof(smp->prnd), smp->prnd); 1550 return 0; 1551 } 1552 1553 return sc_passkey_send_confirm(smp); 1554 1555 case SMP_CMD_PUBLIC_KEY: 1556 default: 1557 /* Initiating device starts the round */ 1558 if (!hcon->out) 1559 return 0; 1560 1561 BT_DBG("%s Starting passkey round %u", hdev->name, 1562 smp->passkey_round + 1); 1563 1564 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1565 1566 return sc_passkey_send_confirm(smp); 1567 } 1568 1569 return 0; 1570 } 1571 1572 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) 1573 { 1574 struct l2cap_conn *conn = smp->conn; 1575 struct hci_conn *hcon = conn->hcon; 1576 u8 smp_op; 1577 1578 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags); 1579 1580 switch (mgmt_op) { 1581 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1582 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); 1583 return 0; 1584 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1585 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); 1586 return 0; 1587 case MGMT_OP_USER_PASSKEY_REPLY: 1588 hcon->passkey_notify = le32_to_cpu(passkey); 1589 smp->passkey_round = 0; 1590 1591 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) 1592 smp_op = SMP_CMD_PAIRING_CONFIRM; 1593 else 1594 smp_op = 0; 1595 1596 if (sc_passkey_round(smp, smp_op)) 1597 return -EIO; 1598 1599 return 0; 1600 } 1601 1602 /* Initiator sends DHKey check first */ 1603 if (hcon->out) { 1604 sc_dhkey_check(smp); 1605 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1606 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) { 1607 sc_dhkey_check(smp); 1608 sc_add_ltk(smp); 1609 } 1610 1611 return 0; 1612 } 1613 1614 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) 1615 { 1616 struct l2cap_conn *conn = hcon->l2cap_data; 1617 struct l2cap_chan *chan; 1618 struct smp_chan *smp; 1619 u32 value; 1620 int err; 1621 1622 BT_DBG(""); 1623 1624 if (!conn) 1625 return -ENOTCONN; 1626 1627 chan = conn->smp; 1628 if (!chan) 1629 return -ENOTCONN; 1630 1631 l2cap_chan_lock(chan); 1632 if (!chan->data) { 1633 err = -ENOTCONN; 1634 goto unlock; 1635 } 1636 1637 smp = chan->data; 1638 1639 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1640 err = sc_user_reply(smp, mgmt_op, passkey); 1641 goto unlock; 1642 } 1643 1644 switch (mgmt_op) { 1645 case MGMT_OP_USER_PASSKEY_REPLY: 1646 value = le32_to_cpu(passkey); 1647 memset(smp->tk, 0, sizeof(smp->tk)); 1648 BT_DBG("PassKey: %d", value); 1649 put_unaligned_le32(value, smp->tk); 1650 /* Fall Through */ 1651 case MGMT_OP_USER_CONFIRM_REPLY: 1652 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 1653 break; 1654 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1655 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1656 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1657 err = 0; 1658 goto unlock; 1659 default: 1660 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1661 err = -EOPNOTSUPP; 1662 goto unlock; 1663 } 1664 1665 err = 0; 1666 1667 /* If it is our turn to send Pairing Confirm, do so now */ 1668 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { 1669 u8 rsp = smp_confirm(smp); 1670 if (rsp) 1671 smp_failure(conn, rsp); 1672 } 1673 1674 unlock: 1675 l2cap_chan_unlock(chan); 1676 return err; 1677 } 1678 1679 static void build_bredr_pairing_cmd(struct smp_chan *smp, 1680 struct smp_cmd_pairing *req, 1681 struct smp_cmd_pairing *rsp) 1682 { 1683 struct l2cap_conn *conn = smp->conn; 1684 struct hci_dev *hdev = conn->hcon->hdev; 1685 u8 local_dist = 0, remote_dist = 0; 1686 1687 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 1688 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1689 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1690 } 1691 1692 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 1693 remote_dist |= SMP_DIST_ID_KEY; 1694 1695 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 1696 local_dist |= SMP_DIST_ID_KEY; 1697 1698 if (!rsp) { 1699 memset(req, 0, sizeof(*req)); 1700 1701 req->auth_req = SMP_AUTH_CT2; 1702 req->init_key_dist = local_dist; 1703 req->resp_key_dist = remote_dist; 1704 req->max_key_size = conn->hcon->enc_key_size; 1705 1706 smp->remote_key_dist = remote_dist; 1707 1708 return; 1709 } 1710 1711 memset(rsp, 0, sizeof(*rsp)); 1712 1713 rsp->auth_req = SMP_AUTH_CT2; 1714 rsp->max_key_size = conn->hcon->enc_key_size; 1715 rsp->init_key_dist = req->init_key_dist & remote_dist; 1716 rsp->resp_key_dist = req->resp_key_dist & local_dist; 1717 1718 smp->remote_key_dist = rsp->init_key_dist; 1719 } 1720 1721 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) 1722 { 1723 struct smp_cmd_pairing rsp, *req = (void *) skb->data; 1724 struct l2cap_chan *chan = conn->smp; 1725 struct hci_dev *hdev = conn->hcon->hdev; 1726 struct smp_chan *smp; 1727 u8 key_size, auth, sec_level; 1728 int ret; 1729 1730 BT_DBG("conn %p", conn); 1731 1732 if (skb->len < sizeof(*req)) 1733 return SMP_INVALID_PARAMS; 1734 1735 if (conn->hcon->role != HCI_ROLE_SLAVE) 1736 return SMP_CMD_NOTSUPP; 1737 1738 if (!chan->data) 1739 smp = smp_chan_create(conn); 1740 else 1741 smp = chan->data; 1742 1743 if (!smp) 1744 return SMP_UNSPECIFIED; 1745 1746 /* We didn't start the pairing, so match remote */ 1747 auth = req->auth_req & AUTH_REQ_MASK(hdev); 1748 1749 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 1750 (auth & SMP_AUTH_BONDING)) 1751 return SMP_PAIRING_NOTSUPP; 1752 1753 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1754 return SMP_AUTH_REQUIREMENTS; 1755 1756 smp->preq[0] = SMP_CMD_PAIRING_REQ; 1757 memcpy(&smp->preq[1], req, sizeof(*req)); 1758 skb_pull(skb, sizeof(*req)); 1759 1760 /* If the remote side's OOB flag is set it means it has 1761 * successfully received our local OOB data - therefore set the 1762 * flag to indicate that local OOB is in use. 1763 */ 1764 if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1765 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1766 1767 /* SMP over BR/EDR requires special treatment */ 1768 if (conn->hcon->type == ACL_LINK) { 1769 /* We must have a BR/EDR SC link */ 1770 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) && 1771 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 1772 return SMP_CROSS_TRANSP_NOT_ALLOWED; 1773 1774 set_bit(SMP_FLAG_SC, &smp->flags); 1775 1776 build_bredr_pairing_cmd(smp, req, &rsp); 1777 1778 if (req->auth_req & SMP_AUTH_CT2) 1779 set_bit(SMP_FLAG_CT2, &smp->flags); 1780 1781 key_size = min(req->max_key_size, rsp.max_key_size); 1782 if (check_enc_key_size(conn, key_size)) 1783 return SMP_ENC_KEY_SIZE; 1784 1785 /* Clear bits which are generated but not distributed */ 1786 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1787 1788 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1789 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1790 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1791 1792 smp_distribute_keys(smp); 1793 return 0; 1794 } 1795 1796 build_pairing_cmd(conn, req, &rsp, auth); 1797 1798 if (rsp.auth_req & SMP_AUTH_SC) { 1799 set_bit(SMP_FLAG_SC, &smp->flags); 1800 1801 if (rsp.auth_req & SMP_AUTH_CT2) 1802 set_bit(SMP_FLAG_CT2, &smp->flags); 1803 } 1804 1805 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 1806 sec_level = BT_SECURITY_MEDIUM; 1807 else 1808 sec_level = authreq_to_seclevel(auth); 1809 1810 if (sec_level > conn->hcon->pending_sec_level) 1811 conn->hcon->pending_sec_level = sec_level; 1812 1813 /* If we need MITM check that it can be achieved */ 1814 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1815 u8 method; 1816 1817 method = get_auth_method(smp, conn->hcon->io_capability, 1818 req->io_capability); 1819 if (method == JUST_WORKS || method == JUST_CFM) 1820 return SMP_AUTH_REQUIREMENTS; 1821 } 1822 1823 key_size = min(req->max_key_size, rsp.max_key_size); 1824 if (check_enc_key_size(conn, key_size)) 1825 return SMP_ENC_KEY_SIZE; 1826 1827 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1828 1829 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1830 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1831 1832 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1833 1834 clear_bit(SMP_FLAG_INITIATOR, &smp->flags); 1835 1836 /* Strictly speaking we shouldn't allow Pairing Confirm for the 1837 * SC case, however some implementations incorrectly copy RFU auth 1838 * req bits from our security request, which may create a false 1839 * positive SC enablement. 1840 */ 1841 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1842 1843 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1844 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1845 /* Clear bits which are generated but not distributed */ 1846 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1847 /* Wait for Public Key from Initiating Device */ 1848 return 0; 1849 } 1850 1851 /* Request setup of TK */ 1852 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); 1853 if (ret) 1854 return SMP_UNSPECIFIED; 1855 1856 return 0; 1857 } 1858 1859 static u8 sc_send_public_key(struct smp_chan *smp) 1860 { 1861 struct hci_dev *hdev = smp->conn->hcon->hdev; 1862 1863 BT_DBG(""); 1864 1865 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 1866 struct l2cap_chan *chan = hdev->smp_data; 1867 struct smp_dev *smp_dev; 1868 1869 if (!chan || !chan->data) 1870 return SMP_UNSPECIFIED; 1871 1872 smp_dev = chan->data; 1873 1874 memcpy(smp->local_pk, smp_dev->local_pk, 64); 1875 memcpy(smp->lr, smp_dev->local_rand, 16); 1876 1877 if (smp_dev->debug_key) 1878 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1879 1880 goto done; 1881 } 1882 1883 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 1884 BT_DBG("Using debug keys"); 1885 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk)) 1886 return SMP_UNSPECIFIED; 1887 memcpy(smp->local_pk, debug_pk, 64); 1888 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1889 } else { 1890 while (true) { 1891 /* Generate key pair for Secure Connections */ 1892 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk)) 1893 return SMP_UNSPECIFIED; 1894 1895 /* This is unlikely, but we need to check that 1896 * we didn't accidentially generate a debug key. 1897 */ 1898 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 1899 break; 1900 } 1901 } 1902 1903 done: 1904 SMP_DBG("Local Public Key X: %32phN", smp->local_pk); 1905 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32); 1906 1907 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); 1908 1909 return 0; 1910 } 1911 1912 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) 1913 { 1914 struct smp_cmd_pairing *req, *rsp = (void *) skb->data; 1915 struct l2cap_chan *chan = conn->smp; 1916 struct smp_chan *smp = chan->data; 1917 struct hci_dev *hdev = conn->hcon->hdev; 1918 u8 key_size, auth; 1919 int ret; 1920 1921 BT_DBG("conn %p", conn); 1922 1923 if (skb->len < sizeof(*rsp)) 1924 return SMP_INVALID_PARAMS; 1925 1926 if (conn->hcon->role != HCI_ROLE_MASTER) 1927 return SMP_CMD_NOTSUPP; 1928 1929 skb_pull(skb, sizeof(*rsp)); 1930 1931 req = (void *) &smp->preq[1]; 1932 1933 key_size = min(req->max_key_size, rsp->max_key_size); 1934 if (check_enc_key_size(conn, key_size)) 1935 return SMP_ENC_KEY_SIZE; 1936 1937 auth = rsp->auth_req & AUTH_REQ_MASK(hdev); 1938 1939 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1940 return SMP_AUTH_REQUIREMENTS; 1941 1942 /* If the remote side's OOB flag is set it means it has 1943 * successfully received our local OOB data - therefore set the 1944 * flag to indicate that local OOB is in use. 1945 */ 1946 if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1947 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1948 1949 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1950 memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); 1951 1952 /* Update remote key distribution in case the remote cleared 1953 * some bits that we had enabled in our request. 1954 */ 1955 smp->remote_key_dist &= rsp->resp_key_dist; 1956 1957 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2)) 1958 set_bit(SMP_FLAG_CT2, &smp->flags); 1959 1960 /* For BR/EDR this means we're done and can start phase 3 */ 1961 if (conn->hcon->type == ACL_LINK) { 1962 /* Clear bits which are generated but not distributed */ 1963 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1964 smp_distribute_keys(smp); 1965 return 0; 1966 } 1967 1968 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) 1969 set_bit(SMP_FLAG_SC, &smp->flags); 1970 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) 1971 conn->hcon->pending_sec_level = BT_SECURITY_HIGH; 1972 1973 /* If we need MITM check that it can be achieved */ 1974 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1975 u8 method; 1976 1977 method = get_auth_method(smp, req->io_capability, 1978 rsp->io_capability); 1979 if (method == JUST_WORKS || method == JUST_CFM) 1980 return SMP_AUTH_REQUIREMENTS; 1981 } 1982 1983 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1984 1985 /* Update remote key distribution in case the remote cleared 1986 * some bits that we had enabled in our request. 1987 */ 1988 smp->remote_key_dist &= rsp->resp_key_dist; 1989 1990 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1991 /* Clear bits which are generated but not distributed */ 1992 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1993 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1994 return sc_send_public_key(smp); 1995 } 1996 1997 auth |= req->auth_req; 1998 1999 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); 2000 if (ret) 2001 return SMP_UNSPECIFIED; 2002 2003 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2004 2005 /* Can't compose response until we have been confirmed */ 2006 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2007 return smp_confirm(smp); 2008 2009 return 0; 2010 } 2011 2012 static u8 sc_check_confirm(struct smp_chan *smp) 2013 { 2014 struct l2cap_conn *conn = smp->conn; 2015 2016 BT_DBG(""); 2017 2018 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2019 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM); 2020 2021 if (conn->hcon->out) { 2022 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2023 smp->prnd); 2024 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2025 } 2026 2027 return 0; 2028 } 2029 2030 /* Work-around for some implementations that incorrectly copy RFU bits 2031 * from our security request and thereby create the impression that 2032 * we're doing SC when in fact the remote doesn't support it. 2033 */ 2034 static int fixup_sc_false_positive(struct smp_chan *smp) 2035 { 2036 struct l2cap_conn *conn = smp->conn; 2037 struct hci_conn *hcon = conn->hcon; 2038 struct hci_dev *hdev = hcon->hdev; 2039 struct smp_cmd_pairing *req, *rsp; 2040 u8 auth; 2041 2042 /* The issue is only observed when we're in slave role */ 2043 if (hcon->out) 2044 return SMP_UNSPECIFIED; 2045 2046 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) { 2047 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode"); 2048 return SMP_UNSPECIFIED; 2049 } 2050 2051 bt_dev_err(hdev, "trying to fall back to legacy SMP"); 2052 2053 req = (void *) &smp->preq[1]; 2054 rsp = (void *) &smp->prsp[1]; 2055 2056 /* Rebuild key dist flags which may have been cleared for SC */ 2057 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist); 2058 2059 auth = req->auth_req & AUTH_REQ_MASK(hdev); 2060 2061 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) { 2062 bt_dev_err(hdev, "failed to fall back to legacy SMP"); 2063 return SMP_UNSPECIFIED; 2064 } 2065 2066 clear_bit(SMP_FLAG_SC, &smp->flags); 2067 2068 return 0; 2069 } 2070 2071 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) 2072 { 2073 struct l2cap_chan *chan = conn->smp; 2074 struct smp_chan *smp = chan->data; 2075 2076 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 2077 2078 if (skb->len < sizeof(smp->pcnf)) 2079 return SMP_INVALID_PARAMS; 2080 2081 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); 2082 skb_pull(skb, sizeof(smp->pcnf)); 2083 2084 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2085 int ret; 2086 2087 /* Public Key exchange must happen before any other steps */ 2088 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) 2089 return sc_check_confirm(smp); 2090 2091 BT_ERR("Unexpected SMP Pairing Confirm"); 2092 2093 ret = fixup_sc_false_positive(smp); 2094 if (ret) 2095 return ret; 2096 } 2097 2098 if (conn->hcon->out) { 2099 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2100 smp->prnd); 2101 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2102 return 0; 2103 } 2104 2105 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2106 return smp_confirm(smp); 2107 2108 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2109 2110 return 0; 2111 } 2112 2113 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) 2114 { 2115 struct l2cap_chan *chan = conn->smp; 2116 struct smp_chan *smp = chan->data; 2117 struct hci_conn *hcon = conn->hcon; 2118 u8 *pkax, *pkbx, *na, *nb; 2119 u32 passkey; 2120 int err; 2121 2122 BT_DBG("conn %p", conn); 2123 2124 if (skb->len < sizeof(smp->rrnd)) 2125 return SMP_INVALID_PARAMS; 2126 2127 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); 2128 skb_pull(skb, sizeof(smp->rrnd)); 2129 2130 if (!test_bit(SMP_FLAG_SC, &smp->flags)) 2131 return smp_random(smp); 2132 2133 if (hcon->out) { 2134 pkax = smp->local_pk; 2135 pkbx = smp->remote_pk; 2136 na = smp->prnd; 2137 nb = smp->rrnd; 2138 } else { 2139 pkax = smp->remote_pk; 2140 pkbx = smp->local_pk; 2141 na = smp->rrnd; 2142 nb = smp->prnd; 2143 } 2144 2145 if (smp->method == REQ_OOB) { 2146 if (!hcon->out) 2147 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2148 sizeof(smp->prnd), smp->prnd); 2149 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2150 goto mackey_and_ltk; 2151 } 2152 2153 /* Passkey entry has special treatment */ 2154 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2155 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM); 2156 2157 if (hcon->out) { 2158 u8 cfm[16]; 2159 2160 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 2161 smp->rrnd, 0, cfm); 2162 if (err) 2163 return SMP_UNSPECIFIED; 2164 2165 if (crypto_memneq(smp->pcnf, cfm, 16)) 2166 return SMP_CONFIRM_FAILED; 2167 } else { 2168 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2169 smp->prnd); 2170 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2171 } 2172 2173 mackey_and_ltk: 2174 /* Generate MacKey and LTK */ 2175 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk); 2176 if (err) 2177 return SMP_UNSPECIFIED; 2178 2179 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) { 2180 if (hcon->out) { 2181 sc_dhkey_check(smp); 2182 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2183 } 2184 return 0; 2185 } 2186 2187 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey); 2188 if (err) 2189 return SMP_UNSPECIFIED; 2190 2191 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type, 2192 hcon->dst_type, passkey, 0); 2193 if (err) 2194 return SMP_UNSPECIFIED; 2195 2196 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2197 2198 return 0; 2199 } 2200 2201 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) 2202 { 2203 struct smp_ltk *key; 2204 struct hci_conn *hcon = conn->hcon; 2205 2206 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); 2207 if (!key) 2208 return false; 2209 2210 if (smp_ltk_sec_level(key) < sec_level) 2211 return false; 2212 2213 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 2214 return true; 2215 2216 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size); 2217 hcon->enc_key_size = key->enc_size; 2218 2219 /* We never store STKs for master role, so clear this flag */ 2220 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 2221 2222 return true; 2223 } 2224 2225 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, 2226 enum smp_key_pref key_pref) 2227 { 2228 if (sec_level == BT_SECURITY_LOW) 2229 return true; 2230 2231 /* If we're encrypted with an STK but the caller prefers using 2232 * LTK claim insufficient security. This way we allow the 2233 * connection to be re-encrypted with an LTK, even if the LTK 2234 * provides the same level of security. Only exception is if we 2235 * don't have an LTK (e.g. because of key distribution bits). 2236 */ 2237 if (key_pref == SMP_USE_LTK && 2238 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && 2239 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) 2240 return false; 2241 2242 if (hcon->sec_level >= sec_level) 2243 return true; 2244 2245 return false; 2246 } 2247 2248 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) 2249 { 2250 struct smp_cmd_security_req *rp = (void *) skb->data; 2251 struct smp_cmd_pairing cp; 2252 struct hci_conn *hcon = conn->hcon; 2253 struct hci_dev *hdev = hcon->hdev; 2254 struct smp_chan *smp; 2255 u8 sec_level, auth; 2256 2257 BT_DBG("conn %p", conn); 2258 2259 if (skb->len < sizeof(*rp)) 2260 return SMP_INVALID_PARAMS; 2261 2262 if (hcon->role != HCI_ROLE_MASTER) 2263 return SMP_CMD_NOTSUPP; 2264 2265 auth = rp->auth_req & AUTH_REQ_MASK(hdev); 2266 2267 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 2268 return SMP_AUTH_REQUIREMENTS; 2269 2270 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 2271 sec_level = BT_SECURITY_MEDIUM; 2272 else 2273 sec_level = authreq_to_seclevel(auth); 2274 2275 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) { 2276 /* If link is already encrypted with sufficient security we 2277 * still need refresh encryption as per Core Spec 5.0 Vol 3, 2278 * Part H 2.4.6 2279 */ 2280 smp_ltk_encrypt(conn, hcon->sec_level); 2281 return 0; 2282 } 2283 2284 if (sec_level > hcon->pending_sec_level) 2285 hcon->pending_sec_level = sec_level; 2286 2287 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2288 return 0; 2289 2290 smp = smp_chan_create(conn); 2291 if (!smp) 2292 return SMP_UNSPECIFIED; 2293 2294 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 2295 (auth & SMP_AUTH_BONDING)) 2296 return SMP_PAIRING_NOTSUPP; 2297 2298 skb_pull(skb, sizeof(*rp)); 2299 2300 memset(&cp, 0, sizeof(cp)); 2301 build_pairing_cmd(conn, &cp, NULL, auth); 2302 2303 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2304 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2305 2306 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2307 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2308 2309 return 0; 2310 } 2311 2312 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) 2313 { 2314 struct l2cap_conn *conn = hcon->l2cap_data; 2315 struct l2cap_chan *chan; 2316 struct smp_chan *smp; 2317 __u8 authreq; 2318 int ret; 2319 2320 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); 2321 2322 /* This may be NULL if there's an unexpected disconnection */ 2323 if (!conn) 2324 return 1; 2325 2326 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) 2327 return 1; 2328 2329 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2330 return 1; 2331 2332 if (sec_level > hcon->pending_sec_level) 2333 hcon->pending_sec_level = sec_level; 2334 2335 if (hcon->role == HCI_ROLE_MASTER) 2336 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2337 return 0; 2338 2339 chan = conn->smp; 2340 if (!chan) { 2341 bt_dev_err(hcon->hdev, "security requested but not available"); 2342 return 1; 2343 } 2344 2345 l2cap_chan_lock(chan); 2346 2347 /* If SMP is already in progress ignore this request */ 2348 if (chan->data) { 2349 ret = 0; 2350 goto unlock; 2351 } 2352 2353 smp = smp_chan_create(conn); 2354 if (!smp) { 2355 ret = 1; 2356 goto unlock; 2357 } 2358 2359 authreq = seclevel_to_authreq(sec_level); 2360 2361 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) { 2362 authreq |= SMP_AUTH_SC; 2363 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED)) 2364 authreq |= SMP_AUTH_CT2; 2365 } 2366 2367 /* Require MITM if IO Capability allows or the security level 2368 * requires it. 2369 */ 2370 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || 2371 hcon->pending_sec_level > BT_SECURITY_MEDIUM) 2372 authreq |= SMP_AUTH_MITM; 2373 2374 if (hcon->role == HCI_ROLE_MASTER) { 2375 struct smp_cmd_pairing cp; 2376 2377 build_pairing_cmd(conn, &cp, NULL, authreq); 2378 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2379 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2380 2381 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2382 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2383 } else { 2384 struct smp_cmd_security_req cp; 2385 cp.auth_req = authreq; 2386 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); 2387 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); 2388 } 2389 2390 set_bit(SMP_FLAG_INITIATOR, &smp->flags); 2391 ret = 0; 2392 2393 unlock: 2394 l2cap_chan_unlock(chan); 2395 return ret; 2396 } 2397 2398 int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr, 2399 u8 addr_type) 2400 { 2401 struct hci_conn *hcon; 2402 struct l2cap_conn *conn; 2403 struct l2cap_chan *chan; 2404 struct smp_chan *smp; 2405 int err; 2406 2407 err = hci_remove_ltk(hdev, bdaddr, addr_type); 2408 hci_remove_irk(hdev, bdaddr, addr_type); 2409 2410 hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type); 2411 if (!hcon) 2412 goto done; 2413 2414 conn = hcon->l2cap_data; 2415 if (!conn) 2416 goto done; 2417 2418 chan = conn->smp; 2419 if (!chan) 2420 goto done; 2421 2422 l2cap_chan_lock(chan); 2423 2424 smp = chan->data; 2425 if (smp) { 2426 /* Set keys to NULL to make sure smp_failure() does not try to 2427 * remove and free already invalidated rcu list entries. */ 2428 smp->ltk = NULL; 2429 smp->slave_ltk = NULL; 2430 smp->remote_irk = NULL; 2431 2432 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) 2433 smp_failure(conn, 0); 2434 else 2435 smp_failure(conn, SMP_UNSPECIFIED); 2436 err = 0; 2437 } 2438 2439 l2cap_chan_unlock(chan); 2440 2441 done: 2442 return err; 2443 } 2444 2445 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) 2446 { 2447 struct smp_cmd_encrypt_info *rp = (void *) skb->data; 2448 struct l2cap_chan *chan = conn->smp; 2449 struct smp_chan *smp = chan->data; 2450 2451 BT_DBG("conn %p", conn); 2452 2453 if (skb->len < sizeof(*rp)) 2454 return SMP_INVALID_PARAMS; 2455 2456 /* Pairing is aborted if any blocked keys are distributed */ 2457 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_LTK, 2458 rp->ltk)) { 2459 bt_dev_warn_ratelimited(conn->hcon->hdev, 2460 "LTK blocked for %pMR", 2461 &conn->hcon->dst); 2462 return SMP_INVALID_PARAMS; 2463 } 2464 2465 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT); 2466 2467 skb_pull(skb, sizeof(*rp)); 2468 2469 memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); 2470 2471 return 0; 2472 } 2473 2474 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) 2475 { 2476 struct smp_cmd_master_ident *rp = (void *) skb->data; 2477 struct l2cap_chan *chan = conn->smp; 2478 struct smp_chan *smp = chan->data; 2479 struct hci_dev *hdev = conn->hcon->hdev; 2480 struct hci_conn *hcon = conn->hcon; 2481 struct smp_ltk *ltk; 2482 u8 authenticated; 2483 2484 BT_DBG("conn %p", conn); 2485 2486 if (skb->len < sizeof(*rp)) 2487 return SMP_INVALID_PARAMS; 2488 2489 /* Mark the information as received */ 2490 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; 2491 2492 if (smp->remote_key_dist & SMP_DIST_ID_KEY) 2493 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 2494 else if (smp->remote_key_dist & SMP_DIST_SIGN) 2495 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2496 2497 skb_pull(skb, sizeof(*rp)); 2498 2499 authenticated = (hcon->sec_level == BT_SECURITY_HIGH); 2500 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, 2501 authenticated, smp->tk, smp->enc_key_size, 2502 rp->ediv, rp->rand); 2503 smp->ltk = ltk; 2504 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2505 smp_distribute_keys(smp); 2506 2507 return 0; 2508 } 2509 2510 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) 2511 { 2512 struct smp_cmd_ident_info *info = (void *) skb->data; 2513 struct l2cap_chan *chan = conn->smp; 2514 struct smp_chan *smp = chan->data; 2515 2516 BT_DBG(""); 2517 2518 if (skb->len < sizeof(*info)) 2519 return SMP_INVALID_PARAMS; 2520 2521 /* Pairing is aborted if any blocked keys are distributed */ 2522 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_IRK, 2523 info->irk)) { 2524 bt_dev_warn_ratelimited(conn->hcon->hdev, 2525 "Identity key blocked for %pMR", 2526 &conn->hcon->dst); 2527 return SMP_INVALID_PARAMS; 2528 } 2529 2530 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); 2531 2532 skb_pull(skb, sizeof(*info)); 2533 2534 memcpy(smp->irk, info->irk, 16); 2535 2536 return 0; 2537 } 2538 2539 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, 2540 struct sk_buff *skb) 2541 { 2542 struct smp_cmd_ident_addr_info *info = (void *) skb->data; 2543 struct l2cap_chan *chan = conn->smp; 2544 struct smp_chan *smp = chan->data; 2545 struct hci_conn *hcon = conn->hcon; 2546 bdaddr_t rpa; 2547 2548 BT_DBG(""); 2549 2550 if (skb->len < sizeof(*info)) 2551 return SMP_INVALID_PARAMS; 2552 2553 /* Mark the information as received */ 2554 smp->remote_key_dist &= ~SMP_DIST_ID_KEY; 2555 2556 if (smp->remote_key_dist & SMP_DIST_SIGN) 2557 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2558 2559 skb_pull(skb, sizeof(*info)); 2560 2561 /* Strictly speaking the Core Specification (4.1) allows sending 2562 * an empty address which would force us to rely on just the IRK 2563 * as "identity information". However, since such 2564 * implementations are not known of and in order to not over 2565 * complicate our implementation, simply pretend that we never 2566 * received an IRK for such a device. 2567 * 2568 * The Identity Address must also be a Static Random or Public 2569 * Address, which hci_is_identity_address() checks for. 2570 */ 2571 if (!bacmp(&info->bdaddr, BDADDR_ANY) || 2572 !hci_is_identity_address(&info->bdaddr, info->addr_type)) { 2573 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address"); 2574 goto distribute; 2575 } 2576 2577 /* Drop IRK if peer is using identity address during pairing but is 2578 * providing different address as identity information. 2579 * 2580 * Microsoft Surface Precision Mouse is known to have this bug. 2581 */ 2582 if (hci_is_identity_address(&hcon->dst, hcon->dst_type) && 2583 (bacmp(&info->bdaddr, &hcon->dst) || 2584 info->addr_type != hcon->dst_type)) { 2585 bt_dev_err(hcon->hdev, 2586 "ignoring IRK with invalid identity address"); 2587 goto distribute; 2588 } 2589 2590 bacpy(&smp->id_addr, &info->bdaddr); 2591 smp->id_addr_type = info->addr_type; 2592 2593 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) 2594 bacpy(&rpa, &hcon->dst); 2595 else 2596 bacpy(&rpa, BDADDR_ANY); 2597 2598 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, 2599 smp->id_addr_type, smp->irk, &rpa); 2600 2601 distribute: 2602 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2603 smp_distribute_keys(smp); 2604 2605 return 0; 2606 } 2607 2608 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) 2609 { 2610 struct smp_cmd_sign_info *rp = (void *) skb->data; 2611 struct l2cap_chan *chan = conn->smp; 2612 struct smp_chan *smp = chan->data; 2613 struct smp_csrk *csrk; 2614 2615 BT_DBG("conn %p", conn); 2616 2617 if (skb->len < sizeof(*rp)) 2618 return SMP_INVALID_PARAMS; 2619 2620 /* Mark the information as received */ 2621 smp->remote_key_dist &= ~SMP_DIST_SIGN; 2622 2623 skb_pull(skb, sizeof(*rp)); 2624 2625 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 2626 if (csrk) { 2627 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM) 2628 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED; 2629 else 2630 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED; 2631 memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); 2632 } 2633 smp->csrk = csrk; 2634 smp_distribute_keys(smp); 2635 2636 return 0; 2637 } 2638 2639 static u8 sc_select_method(struct smp_chan *smp) 2640 { 2641 struct l2cap_conn *conn = smp->conn; 2642 struct hci_conn *hcon = conn->hcon; 2643 struct smp_cmd_pairing *local, *remote; 2644 u8 local_mitm, remote_mitm, local_io, remote_io, method; 2645 2646 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) || 2647 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) 2648 return REQ_OOB; 2649 2650 /* The preq/prsp contain the raw Pairing Request/Response PDUs 2651 * which are needed as inputs to some crypto functions. To get 2652 * the "struct smp_cmd_pairing" from them we need to skip the 2653 * first byte which contains the opcode. 2654 */ 2655 if (hcon->out) { 2656 local = (void *) &smp->preq[1]; 2657 remote = (void *) &smp->prsp[1]; 2658 } else { 2659 local = (void *) &smp->prsp[1]; 2660 remote = (void *) &smp->preq[1]; 2661 } 2662 2663 local_io = local->io_capability; 2664 remote_io = remote->io_capability; 2665 2666 local_mitm = (local->auth_req & SMP_AUTH_MITM); 2667 remote_mitm = (remote->auth_req & SMP_AUTH_MITM); 2668 2669 /* If either side wants MITM, look up the method from the table, 2670 * otherwise use JUST WORKS. 2671 */ 2672 if (local_mitm || remote_mitm) 2673 method = get_auth_method(smp, local_io, remote_io); 2674 else 2675 method = JUST_WORKS; 2676 2677 /* Don't confirm locally initiated pairing attempts */ 2678 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) 2679 method = JUST_WORKS; 2680 2681 return method; 2682 } 2683 2684 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) 2685 { 2686 struct smp_cmd_public_key *key = (void *) skb->data; 2687 struct hci_conn *hcon = conn->hcon; 2688 struct l2cap_chan *chan = conn->smp; 2689 struct smp_chan *smp = chan->data; 2690 struct hci_dev *hdev = hcon->hdev; 2691 struct crypto_kpp *tfm_ecdh; 2692 struct smp_cmd_pairing_confirm cfm; 2693 int err; 2694 2695 BT_DBG("conn %p", conn); 2696 2697 if (skb->len < sizeof(*key)) 2698 return SMP_INVALID_PARAMS; 2699 2700 memcpy(smp->remote_pk, key, 64); 2701 2702 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) { 2703 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk, 2704 smp->rr, 0, cfm.confirm_val); 2705 if (err) 2706 return SMP_UNSPECIFIED; 2707 2708 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16)) 2709 return SMP_CONFIRM_FAILED; 2710 } 2711 2712 /* Non-initiating device sends its public key after receiving 2713 * the key from the initiating device. 2714 */ 2715 if (!hcon->out) { 2716 err = sc_send_public_key(smp); 2717 if (err) 2718 return err; 2719 } 2720 2721 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk); 2722 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32); 2723 2724 /* Compute the shared secret on the same crypto tfm on which the private 2725 * key was set/generated. 2726 */ 2727 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 2728 struct l2cap_chan *hchan = hdev->smp_data; 2729 struct smp_dev *smp_dev; 2730 2731 if (!hchan || !hchan->data) 2732 return SMP_UNSPECIFIED; 2733 2734 smp_dev = hchan->data; 2735 2736 tfm_ecdh = smp_dev->tfm_ecdh; 2737 } else { 2738 tfm_ecdh = smp->tfm_ecdh; 2739 } 2740 2741 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey)) 2742 return SMP_UNSPECIFIED; 2743 2744 SMP_DBG("DHKey %32phN", smp->dhkey); 2745 2746 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); 2747 2748 smp->method = sc_select_method(smp); 2749 2750 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method); 2751 2752 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */ 2753 if (smp->method == JUST_WORKS || smp->method == JUST_CFM) 2754 hcon->pending_sec_level = BT_SECURITY_MEDIUM; 2755 else 2756 hcon->pending_sec_level = BT_SECURITY_FIPS; 2757 2758 if (!crypto_memneq(debug_pk, smp->remote_pk, 64)) 2759 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 2760 2761 if (smp->method == DSP_PASSKEY) { 2762 get_random_bytes(&hcon->passkey_notify, 2763 sizeof(hcon->passkey_notify)); 2764 hcon->passkey_notify %= 1000000; 2765 hcon->passkey_entered = 0; 2766 smp->passkey_round = 0; 2767 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type, 2768 hcon->dst_type, 2769 hcon->passkey_notify, 2770 hcon->passkey_entered)) 2771 return SMP_UNSPECIFIED; 2772 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2773 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY); 2774 } 2775 2776 if (smp->method == REQ_OOB) { 2777 if (hcon->out) 2778 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2779 sizeof(smp->prnd), smp->prnd); 2780 2781 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2782 2783 return 0; 2784 } 2785 2786 if (hcon->out) 2787 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2788 2789 if (smp->method == REQ_PASSKEY) { 2790 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type, 2791 hcon->dst_type)) 2792 return SMP_UNSPECIFIED; 2793 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2794 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2795 return 0; 2796 } 2797 2798 /* The Initiating device waits for the non-initiating device to 2799 * send the confirm value. 2800 */ 2801 if (conn->hcon->out) 2802 return 0; 2803 2804 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, 2805 0, cfm.confirm_val); 2806 if (err) 2807 return SMP_UNSPECIFIED; 2808 2809 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 2810 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2811 2812 return 0; 2813 } 2814 2815 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) 2816 { 2817 struct smp_cmd_dhkey_check *check = (void *) skb->data; 2818 struct l2cap_chan *chan = conn->smp; 2819 struct hci_conn *hcon = conn->hcon; 2820 struct smp_chan *smp = chan->data; 2821 u8 a[7], b[7], *local_addr, *remote_addr; 2822 u8 io_cap[3], r[16], e[16]; 2823 int err; 2824 2825 BT_DBG("conn %p", conn); 2826 2827 if (skb->len < sizeof(*check)) 2828 return SMP_INVALID_PARAMS; 2829 2830 memcpy(a, &hcon->init_addr, 6); 2831 memcpy(b, &hcon->resp_addr, 6); 2832 a[6] = hcon->init_addr_type; 2833 b[6] = hcon->resp_addr_type; 2834 2835 if (hcon->out) { 2836 local_addr = a; 2837 remote_addr = b; 2838 memcpy(io_cap, &smp->prsp[1], 3); 2839 } else { 2840 local_addr = b; 2841 remote_addr = a; 2842 memcpy(io_cap, &smp->preq[1], 3); 2843 } 2844 2845 memset(r, 0, sizeof(r)); 2846 2847 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2848 put_unaligned_le32(hcon->passkey_notify, r); 2849 else if (smp->method == REQ_OOB) 2850 memcpy(r, smp->lr, 16); 2851 2852 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, 2853 io_cap, remote_addr, local_addr, e); 2854 if (err) 2855 return SMP_UNSPECIFIED; 2856 2857 if (crypto_memneq(check->e, e, 16)) 2858 return SMP_DHKEY_CHECK_FAILED; 2859 2860 if (!hcon->out) { 2861 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 2862 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags); 2863 return 0; 2864 } 2865 2866 /* Slave sends DHKey check as response to master */ 2867 sc_dhkey_check(smp); 2868 } 2869 2870 sc_add_ltk(smp); 2871 2872 if (hcon->out) { 2873 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); 2874 hcon->enc_key_size = smp->enc_key_size; 2875 } 2876 2877 return 0; 2878 } 2879 2880 static int smp_cmd_keypress_notify(struct l2cap_conn *conn, 2881 struct sk_buff *skb) 2882 { 2883 struct smp_cmd_keypress_notify *kp = (void *) skb->data; 2884 2885 BT_DBG("value 0x%02x", kp->value); 2886 2887 return 0; 2888 } 2889 2890 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) 2891 { 2892 struct l2cap_conn *conn = chan->conn; 2893 struct hci_conn *hcon = conn->hcon; 2894 struct smp_chan *smp; 2895 __u8 code, reason; 2896 int err = 0; 2897 2898 if (skb->len < 1) 2899 return -EILSEQ; 2900 2901 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) { 2902 reason = SMP_PAIRING_NOTSUPP; 2903 goto done; 2904 } 2905 2906 code = skb->data[0]; 2907 skb_pull(skb, sizeof(code)); 2908 2909 smp = chan->data; 2910 2911 if (code > SMP_CMD_MAX) 2912 goto drop; 2913 2914 if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) 2915 goto drop; 2916 2917 /* If we don't have a context the only allowed commands are 2918 * pairing request and security request. 2919 */ 2920 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) 2921 goto drop; 2922 2923 switch (code) { 2924 case SMP_CMD_PAIRING_REQ: 2925 reason = smp_cmd_pairing_req(conn, skb); 2926 break; 2927 2928 case SMP_CMD_PAIRING_FAIL: 2929 smp_failure(conn, 0); 2930 err = -EPERM; 2931 break; 2932 2933 case SMP_CMD_PAIRING_RSP: 2934 reason = smp_cmd_pairing_rsp(conn, skb); 2935 break; 2936 2937 case SMP_CMD_SECURITY_REQ: 2938 reason = smp_cmd_security_req(conn, skb); 2939 break; 2940 2941 case SMP_CMD_PAIRING_CONFIRM: 2942 reason = smp_cmd_pairing_confirm(conn, skb); 2943 break; 2944 2945 case SMP_CMD_PAIRING_RANDOM: 2946 reason = smp_cmd_pairing_random(conn, skb); 2947 break; 2948 2949 case SMP_CMD_ENCRYPT_INFO: 2950 reason = smp_cmd_encrypt_info(conn, skb); 2951 break; 2952 2953 case SMP_CMD_MASTER_IDENT: 2954 reason = smp_cmd_master_ident(conn, skb); 2955 break; 2956 2957 case SMP_CMD_IDENT_INFO: 2958 reason = smp_cmd_ident_info(conn, skb); 2959 break; 2960 2961 case SMP_CMD_IDENT_ADDR_INFO: 2962 reason = smp_cmd_ident_addr_info(conn, skb); 2963 break; 2964 2965 case SMP_CMD_SIGN_INFO: 2966 reason = smp_cmd_sign_info(conn, skb); 2967 break; 2968 2969 case SMP_CMD_PUBLIC_KEY: 2970 reason = smp_cmd_public_key(conn, skb); 2971 break; 2972 2973 case SMP_CMD_DHKEY_CHECK: 2974 reason = smp_cmd_dhkey_check(conn, skb); 2975 break; 2976 2977 case SMP_CMD_KEYPRESS_NOTIFY: 2978 reason = smp_cmd_keypress_notify(conn, skb); 2979 break; 2980 2981 default: 2982 BT_DBG("Unknown command code 0x%2.2x", code); 2983 reason = SMP_CMD_NOTSUPP; 2984 goto done; 2985 } 2986 2987 done: 2988 if (!err) { 2989 if (reason) 2990 smp_failure(conn, reason); 2991 kfree_skb(skb); 2992 } 2993 2994 return err; 2995 2996 drop: 2997 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR", 2998 code, &hcon->dst); 2999 kfree_skb(skb); 3000 return 0; 3001 } 3002 3003 static void smp_teardown_cb(struct l2cap_chan *chan, int err) 3004 { 3005 struct l2cap_conn *conn = chan->conn; 3006 3007 BT_DBG("chan %p", chan); 3008 3009 if (chan->data) 3010 smp_chan_destroy(conn); 3011 3012 conn->smp = NULL; 3013 l2cap_chan_put(chan); 3014 } 3015 3016 static void bredr_pairing(struct l2cap_chan *chan) 3017 { 3018 struct l2cap_conn *conn = chan->conn; 3019 struct hci_conn *hcon = conn->hcon; 3020 struct hci_dev *hdev = hcon->hdev; 3021 struct smp_cmd_pairing req; 3022 struct smp_chan *smp; 3023 3024 BT_DBG("chan %p", chan); 3025 3026 /* Only new pairings are interesting */ 3027 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags)) 3028 return; 3029 3030 /* Don't bother if we're not encrypted */ 3031 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3032 return; 3033 3034 /* Only master may initiate SMP over BR/EDR */ 3035 if (hcon->role != HCI_ROLE_MASTER) 3036 return; 3037 3038 /* Secure Connections support must be enabled */ 3039 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED)) 3040 return; 3041 3042 /* BR/EDR must use Secure Connections for SMP */ 3043 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) && 3044 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3045 return; 3046 3047 /* If our LE support is not enabled don't do anything */ 3048 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) 3049 return; 3050 3051 /* Don't bother if remote LE support is not enabled */ 3052 if (!lmp_host_le_capable(hcon)) 3053 return; 3054 3055 /* Remote must support SMP fixed chan for BR/EDR */ 3056 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR)) 3057 return; 3058 3059 /* Don't bother if SMP is already ongoing */ 3060 if (chan->data) 3061 return; 3062 3063 smp = smp_chan_create(conn); 3064 if (!smp) { 3065 bt_dev_err(hdev, "unable to create SMP context for BR/EDR"); 3066 return; 3067 } 3068 3069 set_bit(SMP_FLAG_SC, &smp->flags); 3070 3071 BT_DBG("%s starting SMP over BR/EDR", hdev->name); 3072 3073 /* Prepare and send the BR/EDR SMP Pairing Request */ 3074 build_bredr_pairing_cmd(smp, &req, NULL); 3075 3076 smp->preq[0] = SMP_CMD_PAIRING_REQ; 3077 memcpy(&smp->preq[1], &req, sizeof(req)); 3078 3079 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req); 3080 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 3081 } 3082 3083 static void smp_resume_cb(struct l2cap_chan *chan) 3084 { 3085 struct smp_chan *smp = chan->data; 3086 struct l2cap_conn *conn = chan->conn; 3087 struct hci_conn *hcon = conn->hcon; 3088 3089 BT_DBG("chan %p", chan); 3090 3091 if (hcon->type == ACL_LINK) { 3092 bredr_pairing(chan); 3093 return; 3094 } 3095 3096 if (!smp) 3097 return; 3098 3099 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3100 return; 3101 3102 cancel_delayed_work(&smp->security_timer); 3103 3104 smp_distribute_keys(smp); 3105 } 3106 3107 static void smp_ready_cb(struct l2cap_chan *chan) 3108 { 3109 struct l2cap_conn *conn = chan->conn; 3110 struct hci_conn *hcon = conn->hcon; 3111 3112 BT_DBG("chan %p", chan); 3113 3114 /* No need to call l2cap_chan_hold() here since we already own 3115 * the reference taken in smp_new_conn_cb(). This is just the 3116 * first time that we tie it to a specific pointer. The code in 3117 * l2cap_core.c ensures that there's no risk this function wont 3118 * get called if smp_new_conn_cb was previously called. 3119 */ 3120 conn->smp = chan; 3121 3122 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3123 bredr_pairing(chan); 3124 } 3125 3126 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 3127 { 3128 int err; 3129 3130 BT_DBG("chan %p", chan); 3131 3132 err = smp_sig_channel(chan, skb); 3133 if (err) { 3134 struct smp_chan *smp = chan->data; 3135 3136 if (smp) 3137 cancel_delayed_work_sync(&smp->security_timer); 3138 3139 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); 3140 } 3141 3142 return err; 3143 } 3144 3145 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, 3146 unsigned long hdr_len, 3147 unsigned long len, int nb) 3148 { 3149 struct sk_buff *skb; 3150 3151 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); 3152 if (!skb) 3153 return ERR_PTR(-ENOMEM); 3154 3155 skb->priority = HCI_PRIO_MAX; 3156 bt_cb(skb)->l2cap.chan = chan; 3157 3158 return skb; 3159 } 3160 3161 static const struct l2cap_ops smp_chan_ops = { 3162 .name = "Security Manager", 3163 .ready = smp_ready_cb, 3164 .recv = smp_recv_cb, 3165 .alloc_skb = smp_alloc_skb_cb, 3166 .teardown = smp_teardown_cb, 3167 .resume = smp_resume_cb, 3168 3169 .new_connection = l2cap_chan_no_new_connection, 3170 .state_change = l2cap_chan_no_state_change, 3171 .close = l2cap_chan_no_close, 3172 .defer = l2cap_chan_no_defer, 3173 .suspend = l2cap_chan_no_suspend, 3174 .set_shutdown = l2cap_chan_no_set_shutdown, 3175 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3176 }; 3177 3178 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) 3179 { 3180 struct l2cap_chan *chan; 3181 3182 BT_DBG("pchan %p", pchan); 3183 3184 chan = l2cap_chan_create(); 3185 if (!chan) 3186 return NULL; 3187 3188 chan->chan_type = pchan->chan_type; 3189 chan->ops = &smp_chan_ops; 3190 chan->scid = pchan->scid; 3191 chan->dcid = chan->scid; 3192 chan->imtu = pchan->imtu; 3193 chan->omtu = pchan->omtu; 3194 chan->mode = pchan->mode; 3195 3196 /* Other L2CAP channels may request SMP routines in order to 3197 * change the security level. This means that the SMP channel 3198 * lock must be considered in its own category to avoid lockdep 3199 * warnings. 3200 */ 3201 atomic_set(&chan->nesting, L2CAP_NESTING_SMP); 3202 3203 BT_DBG("created chan %p", chan); 3204 3205 return chan; 3206 } 3207 3208 static const struct l2cap_ops smp_root_chan_ops = { 3209 .name = "Security Manager Root", 3210 .new_connection = smp_new_conn_cb, 3211 3212 /* None of these are implemented for the root channel */ 3213 .close = l2cap_chan_no_close, 3214 .alloc_skb = l2cap_chan_no_alloc_skb, 3215 .recv = l2cap_chan_no_recv, 3216 .state_change = l2cap_chan_no_state_change, 3217 .teardown = l2cap_chan_no_teardown, 3218 .ready = l2cap_chan_no_ready, 3219 .defer = l2cap_chan_no_defer, 3220 .suspend = l2cap_chan_no_suspend, 3221 .resume = l2cap_chan_no_resume, 3222 .set_shutdown = l2cap_chan_no_set_shutdown, 3223 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3224 }; 3225 3226 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 3227 { 3228 struct l2cap_chan *chan; 3229 struct smp_dev *smp; 3230 struct crypto_shash *tfm_cmac; 3231 struct crypto_kpp *tfm_ecdh; 3232 3233 if (cid == L2CAP_CID_SMP_BREDR) { 3234 smp = NULL; 3235 goto create_chan; 3236 } 3237 3238 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 3239 if (!smp) 3240 return ERR_PTR(-ENOMEM); 3241 3242 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3243 if (IS_ERR(tfm_cmac)) { 3244 BT_ERR("Unable to create CMAC crypto context"); 3245 kzfree(smp); 3246 return ERR_CAST(tfm_cmac); 3247 } 3248 3249 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0); 3250 if (IS_ERR(tfm_ecdh)) { 3251 BT_ERR("Unable to create ECDH crypto context"); 3252 crypto_free_shash(tfm_cmac); 3253 kzfree(smp); 3254 return ERR_CAST(tfm_ecdh); 3255 } 3256 3257 smp->local_oob = false; 3258 smp->tfm_cmac = tfm_cmac; 3259 smp->tfm_ecdh = tfm_ecdh; 3260 3261 create_chan: 3262 chan = l2cap_chan_create(); 3263 if (!chan) { 3264 if (smp) { 3265 crypto_free_shash(smp->tfm_cmac); 3266 crypto_free_kpp(smp->tfm_ecdh); 3267 kzfree(smp); 3268 } 3269 return ERR_PTR(-ENOMEM); 3270 } 3271 3272 chan->data = smp; 3273 3274 l2cap_add_scid(chan, cid); 3275 3276 l2cap_chan_set_defaults(chan); 3277 3278 if (cid == L2CAP_CID_SMP) { 3279 u8 bdaddr_type; 3280 3281 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type); 3282 3283 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 3284 chan->src_type = BDADDR_LE_PUBLIC; 3285 else 3286 chan->src_type = BDADDR_LE_RANDOM; 3287 } else { 3288 bacpy(&chan->src, &hdev->bdaddr); 3289 chan->src_type = BDADDR_BREDR; 3290 } 3291 3292 chan->state = BT_LISTEN; 3293 chan->mode = L2CAP_MODE_BASIC; 3294 chan->imtu = L2CAP_DEFAULT_MTU; 3295 chan->ops = &smp_root_chan_ops; 3296 3297 /* Set correct nesting level for a parent/listening channel */ 3298 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 3299 3300 return chan; 3301 } 3302 3303 static void smp_del_chan(struct l2cap_chan *chan) 3304 { 3305 struct smp_dev *smp; 3306 3307 BT_DBG("chan %p", chan); 3308 3309 smp = chan->data; 3310 if (smp) { 3311 chan->data = NULL; 3312 crypto_free_shash(smp->tfm_cmac); 3313 crypto_free_kpp(smp->tfm_ecdh); 3314 kzfree(smp); 3315 } 3316 3317 l2cap_chan_put(chan); 3318 } 3319 3320 static ssize_t force_bredr_smp_read(struct file *file, 3321 char __user *user_buf, 3322 size_t count, loff_t *ppos) 3323 { 3324 struct hci_dev *hdev = file->private_data; 3325 char buf[3]; 3326 3327 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N'; 3328 buf[1] = '\n'; 3329 buf[2] = '\0'; 3330 return simple_read_from_buffer(user_buf, count, ppos, buf, 2); 3331 } 3332 3333 static ssize_t force_bredr_smp_write(struct file *file, 3334 const char __user *user_buf, 3335 size_t count, loff_t *ppos) 3336 { 3337 struct hci_dev *hdev = file->private_data; 3338 bool enable; 3339 int err; 3340 3341 err = kstrtobool_from_user(user_buf, count, &enable); 3342 if (err) 3343 return err; 3344 3345 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3346 return -EALREADY; 3347 3348 if (enable) { 3349 struct l2cap_chan *chan; 3350 3351 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3352 if (IS_ERR(chan)) 3353 return PTR_ERR(chan); 3354 3355 hdev->smp_bredr_data = chan; 3356 } else { 3357 struct l2cap_chan *chan; 3358 3359 chan = hdev->smp_bredr_data; 3360 hdev->smp_bredr_data = NULL; 3361 smp_del_chan(chan); 3362 } 3363 3364 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP); 3365 3366 return count; 3367 } 3368 3369 static const struct file_operations force_bredr_smp_fops = { 3370 .open = simple_open, 3371 .read = force_bredr_smp_read, 3372 .write = force_bredr_smp_write, 3373 .llseek = default_llseek, 3374 }; 3375 3376 int smp_register(struct hci_dev *hdev) 3377 { 3378 struct l2cap_chan *chan; 3379 3380 BT_DBG("%s", hdev->name); 3381 3382 /* If the controller does not support Low Energy operation, then 3383 * there is also no need to register any SMP channel. 3384 */ 3385 if (!lmp_le_capable(hdev)) 3386 return 0; 3387 3388 if (WARN_ON(hdev->smp_data)) { 3389 chan = hdev->smp_data; 3390 hdev->smp_data = NULL; 3391 smp_del_chan(chan); 3392 } 3393 3394 chan = smp_add_cid(hdev, L2CAP_CID_SMP); 3395 if (IS_ERR(chan)) 3396 return PTR_ERR(chan); 3397 3398 hdev->smp_data = chan; 3399 3400 /* If the controller does not support BR/EDR Secure Connections 3401 * feature, then the BR/EDR SMP channel shall not be present. 3402 * 3403 * To test this with Bluetooth 4.0 controllers, create a debugfs 3404 * switch that allows forcing BR/EDR SMP support and accepting 3405 * cross-transport pairing on non-AES encrypted connections. 3406 */ 3407 if (!lmp_sc_capable(hdev)) { 3408 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs, 3409 hdev, &force_bredr_smp_fops); 3410 3411 /* Flag can be already set here (due to power toggle) */ 3412 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3413 return 0; 3414 } 3415 3416 if (WARN_ON(hdev->smp_bredr_data)) { 3417 chan = hdev->smp_bredr_data; 3418 hdev->smp_bredr_data = NULL; 3419 smp_del_chan(chan); 3420 } 3421 3422 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3423 if (IS_ERR(chan)) { 3424 int err = PTR_ERR(chan); 3425 chan = hdev->smp_data; 3426 hdev->smp_data = NULL; 3427 smp_del_chan(chan); 3428 return err; 3429 } 3430 3431 hdev->smp_bredr_data = chan; 3432 3433 return 0; 3434 } 3435 3436 void smp_unregister(struct hci_dev *hdev) 3437 { 3438 struct l2cap_chan *chan; 3439 3440 if (hdev->smp_bredr_data) { 3441 chan = hdev->smp_bredr_data; 3442 hdev->smp_bredr_data = NULL; 3443 smp_del_chan(chan); 3444 } 3445 3446 if (hdev->smp_data) { 3447 chan = hdev->smp_data; 3448 hdev->smp_data = NULL; 3449 smp_del_chan(chan); 3450 } 3451 } 3452 3453 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) 3454 3455 static int __init test_debug_key(struct crypto_kpp *tfm_ecdh) 3456 { 3457 u8 pk[64]; 3458 int err; 3459 3460 err = set_ecdh_privkey(tfm_ecdh, debug_sk); 3461 if (err) 3462 return err; 3463 3464 err = generate_ecdh_public_key(tfm_ecdh, pk); 3465 if (err) 3466 return err; 3467 3468 if (crypto_memneq(pk, debug_pk, 64)) 3469 return -EINVAL; 3470 3471 return 0; 3472 } 3473 3474 static int __init test_ah(void) 3475 { 3476 const u8 irk[16] = { 3477 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3478 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3479 const u8 r[3] = { 0x94, 0x81, 0x70 }; 3480 const u8 exp[3] = { 0xaa, 0xfb, 0x0d }; 3481 u8 res[3]; 3482 int err; 3483 3484 err = smp_ah(irk, r, res); 3485 if (err) 3486 return err; 3487 3488 if (crypto_memneq(res, exp, 3)) 3489 return -EINVAL; 3490 3491 return 0; 3492 } 3493 3494 static int __init test_c1(void) 3495 { 3496 const u8 k[16] = { 3497 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3498 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3499 const u8 r[16] = { 3500 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63, 3501 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 }; 3502 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 }; 3503 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 }; 3504 const u8 _iat = 0x01; 3505 const u8 _rat = 0x00; 3506 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } }; 3507 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } }; 3508 const u8 exp[16] = { 3509 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2, 3510 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e }; 3511 u8 res[16]; 3512 int err; 3513 3514 err = smp_c1(k, r, preq, pres, _iat, &ia, _rat, &ra, res); 3515 if (err) 3516 return err; 3517 3518 if (crypto_memneq(res, exp, 16)) 3519 return -EINVAL; 3520 3521 return 0; 3522 } 3523 3524 static int __init test_s1(void) 3525 { 3526 const u8 k[16] = { 3527 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3528 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3529 const u8 r1[16] = { 3530 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }; 3531 const u8 r2[16] = { 3532 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 }; 3533 const u8 exp[16] = { 3534 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b, 3535 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a }; 3536 u8 res[16]; 3537 int err; 3538 3539 err = smp_s1(k, r1, r2, res); 3540 if (err) 3541 return err; 3542 3543 if (crypto_memneq(res, exp, 16)) 3544 return -EINVAL; 3545 3546 return 0; 3547 } 3548 3549 static int __init test_f4(struct crypto_shash *tfm_cmac) 3550 { 3551 const u8 u[32] = { 3552 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3553 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3554 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3555 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3556 const u8 v[32] = { 3557 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3558 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3559 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3560 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3561 const u8 x[16] = { 3562 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3563 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3564 const u8 z = 0x00; 3565 const u8 exp[16] = { 3566 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1, 3567 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 }; 3568 u8 res[16]; 3569 int err; 3570 3571 err = smp_f4(tfm_cmac, u, v, x, z, res); 3572 if (err) 3573 return err; 3574 3575 if (crypto_memneq(res, exp, 16)) 3576 return -EINVAL; 3577 3578 return 0; 3579 } 3580 3581 static int __init test_f5(struct crypto_shash *tfm_cmac) 3582 { 3583 const u8 w[32] = { 3584 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86, 3585 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99, 3586 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3587 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3588 const u8 n1[16] = { 3589 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3590 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3591 const u8 n2[16] = { 3592 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3593 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3594 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3595 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3596 const u8 exp_ltk[16] = { 3597 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98, 3598 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 }; 3599 const u8 exp_mackey[16] = { 3600 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3601 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3602 u8 mackey[16], ltk[16]; 3603 int err; 3604 3605 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk); 3606 if (err) 3607 return err; 3608 3609 if (crypto_memneq(mackey, exp_mackey, 16)) 3610 return -EINVAL; 3611 3612 if (crypto_memneq(ltk, exp_ltk, 16)) 3613 return -EINVAL; 3614 3615 return 0; 3616 } 3617 3618 static int __init test_f6(struct crypto_shash *tfm_cmac) 3619 { 3620 const u8 w[16] = { 3621 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3622 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3623 const u8 n1[16] = { 3624 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3625 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3626 const u8 n2[16] = { 3627 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3628 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3629 const u8 r[16] = { 3630 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08, 3631 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 }; 3632 const u8 io_cap[3] = { 0x02, 0x01, 0x01 }; 3633 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3634 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3635 const u8 exp[16] = { 3636 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2, 3637 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 }; 3638 u8 res[16]; 3639 int err; 3640 3641 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res); 3642 if (err) 3643 return err; 3644 3645 if (crypto_memneq(res, exp, 16)) 3646 return -EINVAL; 3647 3648 return 0; 3649 } 3650 3651 static int __init test_g2(struct crypto_shash *tfm_cmac) 3652 { 3653 const u8 u[32] = { 3654 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3655 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3656 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3657 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3658 const u8 v[32] = { 3659 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3660 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3661 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3662 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3663 const u8 x[16] = { 3664 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3665 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3666 const u8 y[16] = { 3667 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3668 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3669 const u32 exp_val = 0x2f9ed5ba % 1000000; 3670 u32 val; 3671 int err; 3672 3673 err = smp_g2(tfm_cmac, u, v, x, y, &val); 3674 if (err) 3675 return err; 3676 3677 if (val != exp_val) 3678 return -EINVAL; 3679 3680 return 0; 3681 } 3682 3683 static int __init test_h6(struct crypto_shash *tfm_cmac) 3684 { 3685 const u8 w[16] = { 3686 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3687 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3688 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c }; 3689 const u8 exp[16] = { 3690 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8, 3691 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d }; 3692 u8 res[16]; 3693 int err; 3694 3695 err = smp_h6(tfm_cmac, w, key_id, res); 3696 if (err) 3697 return err; 3698 3699 if (crypto_memneq(res, exp, 16)) 3700 return -EINVAL; 3701 3702 return 0; 3703 } 3704 3705 static char test_smp_buffer[32]; 3706 3707 static ssize_t test_smp_read(struct file *file, char __user *user_buf, 3708 size_t count, loff_t *ppos) 3709 { 3710 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer, 3711 strlen(test_smp_buffer)); 3712 } 3713 3714 static const struct file_operations test_smp_fops = { 3715 .open = simple_open, 3716 .read = test_smp_read, 3717 .llseek = default_llseek, 3718 }; 3719 3720 static int __init run_selftests(struct crypto_shash *tfm_cmac, 3721 struct crypto_kpp *tfm_ecdh) 3722 { 3723 ktime_t calltime, delta, rettime; 3724 unsigned long long duration; 3725 int err; 3726 3727 calltime = ktime_get(); 3728 3729 err = test_debug_key(tfm_ecdh); 3730 if (err) { 3731 BT_ERR("debug_key test failed"); 3732 goto done; 3733 } 3734 3735 err = test_ah(); 3736 if (err) { 3737 BT_ERR("smp_ah test failed"); 3738 goto done; 3739 } 3740 3741 err = test_c1(); 3742 if (err) { 3743 BT_ERR("smp_c1 test failed"); 3744 goto done; 3745 } 3746 3747 err = test_s1(); 3748 if (err) { 3749 BT_ERR("smp_s1 test failed"); 3750 goto done; 3751 } 3752 3753 err = test_f4(tfm_cmac); 3754 if (err) { 3755 BT_ERR("smp_f4 test failed"); 3756 goto done; 3757 } 3758 3759 err = test_f5(tfm_cmac); 3760 if (err) { 3761 BT_ERR("smp_f5 test failed"); 3762 goto done; 3763 } 3764 3765 err = test_f6(tfm_cmac); 3766 if (err) { 3767 BT_ERR("smp_f6 test failed"); 3768 goto done; 3769 } 3770 3771 err = test_g2(tfm_cmac); 3772 if (err) { 3773 BT_ERR("smp_g2 test failed"); 3774 goto done; 3775 } 3776 3777 err = test_h6(tfm_cmac); 3778 if (err) { 3779 BT_ERR("smp_h6 test failed"); 3780 goto done; 3781 } 3782 3783 rettime = ktime_get(); 3784 delta = ktime_sub(rettime, calltime); 3785 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 3786 3787 BT_INFO("SMP test passed in %llu usecs", duration); 3788 3789 done: 3790 if (!err) 3791 snprintf(test_smp_buffer, sizeof(test_smp_buffer), 3792 "PASS (%llu usecs)\n", duration); 3793 else 3794 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n"); 3795 3796 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL, 3797 &test_smp_fops); 3798 3799 return err; 3800 } 3801 3802 int __init bt_selftest_smp(void) 3803 { 3804 struct crypto_shash *tfm_cmac; 3805 struct crypto_kpp *tfm_ecdh; 3806 int err; 3807 3808 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3809 if (IS_ERR(tfm_cmac)) { 3810 BT_ERR("Unable to create CMAC crypto context"); 3811 return PTR_ERR(tfm_cmac); 3812 } 3813 3814 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0); 3815 if (IS_ERR(tfm_ecdh)) { 3816 BT_ERR("Unable to create ECDH crypto context"); 3817 crypto_free_shash(tfm_cmac); 3818 return PTR_ERR(tfm_ecdh); 3819 } 3820 3821 err = run_selftests(tfm_cmac, tfm_ecdh); 3822 3823 crypto_free_shash(tfm_cmac); 3824 crypto_free_kpp(tfm_ecdh); 3825 3826 return err; 3827 } 3828 3829 #endif 3830